Neuroscience Quiz: Broca's Area and More

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Questions and Answers

Damage to Broca's area, as seen in Hank's case, primarily affects which function?

  • Processing and understanding spoken language.
  • Motor control of speech and word retrieval. (correct)
  • Visual acuity and depth perception.
  • Sensory perception of pain and temperature.

In Brown-Sequard syndrome, as experienced by Steve, a lesion on one side of the spinal cord typically results in:

  • Contralateral weakness and ipsilateral loss of pain and temperature sensation.
  • Loss of proprioception and vibration sense on both sides of the body.
  • Ipsilateral weakness and contralateral loss of pain and temperature sensation. (correct)
  • Bilateral loss of motor function and sensory perception below the lesion.

Which characteristic is most indicative of multiple sclerosis (MS) as described in the text?

  • Damage specifically located within the peripheral nervous system.
  • Interruption of signals within the central nervous system due to variable lesion locations. (correct)
  • Progressive degeneration of motor neurons in the spinal cord and brainstem.
  • A predictable and uniform pattern of neurological deficits across all patients.

Which of the following cell types is classified as a macroglia?

<p>Astrocytes (D)</p> Signup and view all the answers

What is the primary function of ependymal cells within the nervous system?

<p>Lining the ventricles of the brain and aiding in CSF circulation. (A)</p> Signup and view all the answers

Within the context of neuronal communication, what accurately describes the role of the postsynaptic neuron?

<p>It receives signals from the presynaptic neuron. (D)</p> Signup and view all the answers

Which of the following structures is exclusively part of the central nervous system (CNS)?

<p>Spinal cord. (D)</p> Signup and view all the answers

Which of the following is a crucial component defining the junction between two communicating neurons?

<p>Synapse. (A)</p> Signup and view all the answers

Which of the following structures is considered part of the peripheral nervous system (PNS) despite being encased by the vertebral column?

<p>Cauda equina (C)</p> Signup and view all the answers

Which of the following cranial nerves are the exception to the rule that cranial nerves are part of the peripheral nervous system?

<p>Olfactory (I) and Optic (II) (C)</p> Signup and view all the answers

Which of the following accurately describes the function of the autonomic nervous system?

<p>Innervates smooth muscle, cardiac muscle, and glands (C)</p> Signup and view all the answers

Which plane of section would divide the brain into anterior and posterior portions?

<p>Coronal (C)</p> Signup and view all the answers

In the spinal cord, what type of information is primarily processed in the dorsal horns?

<p>Sensory input from the body (D)</p> Signup and view all the answers

Which of the following is NOT considered a part of the brainstem?

<p>Cerebellum (B)</p> Signup and view all the answers

What is the primary function of cerebrospinal fluid (CSF)?

<p>To provide structural support, cushion, and remove waste from the CNS (B)</p> Signup and view all the answers

Which of the following is the most intimate layer of the meninges?

<p>Pia mater (D)</p> Signup and view all the answers

What is the clinical significance of a 'decussation' in the central nervous system?

<p>Damage on one side of the brain may manifest on the opposite side of the body. (C)</p> Signup and view all the answers

Which of the following best describes white matter of the central nervous system (CNS)?

<p>A collection of neuronal axons with myelin sheaths, found in the inner portions of the brain (A)</p> Signup and view all the answers

Which layer of the meninges is avascular?

<p>Arachnoid mater (D)</p> Signup and view all the answers

What is the function of the cerebrospinal fluid (CSF)?

<p>Supplying nutrients, collecting waste products, and cushioning the brain (B)</p> Signup and view all the answers

Which artery supplies the anterior two-thirds of the spinal cord?

<p>Anterior spinal artery (A)</p> Signup and view all the answers

Which arteries form the basilar artery?

<p>Vertebral arteries (C)</p> Signup and view all the answers

Which area of the brain is supplied by the posterior cerebral artery (PCA)?

<p>Occipital lobe (B)</p> Signup and view all the answers

What is a Transient Ischemic Attack (TIA)?

<p>Brief, focal loss of brain function with full recovery within 24 hours (B)</p> Signup and view all the answers

What is a characteristic of an Arteriovenous Malformation (AVM)?

<p>Developmental abnormality with artery or vein connections (D)</p> Signup and view all the answers

What does the blood-brain barrier do?

<p>Prevents pathogens from reaching the CNS (B)</p> Signup and view all the answers

Why does oxygen consumption increase from the brainstem to the cortex?

<p>Higher order functioning areas need more energy (B)</p> Signup and view all the answers

Using a CT scan, what color does bone show up as?

<p>Bright White (A)</p> Signup and view all the answers

What is a common symptom of meningioma?

<p>Seizures (D)</p> Signup and view all the answers

What is meant by diffuse damage?

<p>Widespread throughout the brain (C)</p> Signup and view all the answers

What type of scan shows metabolic function?

<p>PET Scan (B)</p> Signup and view all the answers

What is the difference between overt and occult hydrocephalus

<p>Overt is when the head enlarges, occult is when the head remains normal (C)</p> Signup and view all the answers

Which of the following events can affect the nervous system?

<p>All of the above (D)</p> Signup and view all the answers

Which of the following cranial nerves does not attach to the pons?

<p>IX (Glossopharyngeal) (D)</p> Signup and view all the answers

Which of the following describes the primary function of the ventral horn of the spinal gray matter?

<p>Motor control (C)</p> Signup and view all the answers

What is the main function of the ascending reticular activating system (ARAS)?

<p>Control of the level of consciousness (B)</p> Signup and view all the answers

Which type of neuron is commonly found in sensory spinal nerves and cranial nerve I?

<p>Unipolar/Pseudounipolar (C)</p> Signup and view all the answers

Which of the following describes the primary function of dendrites?

<p>Detecting stimuli (C)</p> Signup and view all the answers

Which of the following structures contains all of the motor tracts?

<p>Pyramids (C)</p> Signup and view all the answers

Which of the following portions of the neuron is also known as the trigger zone?

<p>Axon hillock (B)</p> Signup and view all the answers

Which of the following best describes the effector zone of the reticular formation?

<p>Comprises the medial 2/3 of the RF (D)</p> Signup and view all the answers

In the internal organization of the midbrain, pons, and medulla, which of the following is not a major component?

<p>Cortex (B)</p> Signup and view all the answers

What is the key characteristic of gated channels within the neuron's plasma membrane?

<p>They open and close to regulate ion flow. (A)</p> Signup and view all the answers

What is the primary function of Diffusion Tensor Imaging (DTI)?

<p>Detailed imaging of white matter tracts. (B)</p> Signup and view all the answers

Which neuroimaging technique is MOST suitable for visualizing blood vessels with high detail after injecting a contrast medium?

<p>Magnetic Resonance Angiography (MRA) (B)</p> Signup and view all the answers

The spinal cord extends from the medulla oblongata to which vertebral level?

<p>L1/L2 (D)</p> Signup and view all the answers

Which of the following structures contains cell bodies and a rich capillary network within the spinal cord?

<p>Gray matter (C)</p> Signup and view all the answers

Which of the following statements BEST describes a myotome?

<p>A group of muscles primarily innervated by the motor fibers of a single nerve root. (D)</p> Signup and view all the answers

Which neuroimaging method provides detailed images of soft tissues, while also detecting tumors, infections, and multiple sclerosis lesions?

<p>Magnetic Resonance Imaging (MRI) (D)</p> Signup and view all the answers

What is the function of the filum terminale?

<p>To adhere the bottom of the spinal cord to the coccyx. (B)</p> Signup and view all the answers

At which spinal level is the cervical enlargement located, giving rise to the brachial plexus?

<p>C4-T1 (C)</p> Signup and view all the answers

Which of the following is a primary characteristic of a vertical lesion in the spinal cord?

<p>Interruption of communication between ascending and descending information. (B)</p> Signup and view all the answers

What does the Dorsal Root Ganglion (DRG) contain?

<p>Sensory neuron cell bodies. (A)</p> Signup and view all the answers

The motor fibers of a single nerve root primarily innervate which of the following?

<p>Myotome (D)</p> Signup and view all the answers

Which of the following functions can be assessed using Functional MRI (fMRI)?

<p>Changes in blood flow related to brain function. (A)</p> Signup and view all the answers

Which of the following imaging techniques is contraindicated in patients with metal implants?

<p>Magnetic Resonance Imaging (MRI) (C)</p> Signup and view all the answers

A patient has weakness in their deltoid muscle. Which spinal nerve root is MOST likely affected?

<p>C5 (B)</p> Signup and view all the answers

Which neuroimaging scan is BEST for detecting an ischemic stroke?

<p>Diffusion Tensor Imaging (DTI) (D)</p> Signup and view all the answers

What is the initial effect of an inhibitory local potential on the likelihood of generating an action potential?

<p>It decreases the likelihood by causing hyperpolarization. (B)</p> Signup and view all the answers

Which of the following best describes temporal summation?

<p>The integration of multiple potentials at the same site at different times. (C)</p> Signup and view all the answers

What happens when the summation of local potentials at the axon hillock is sufficient to reach the threshold?

<p>Na+ voltage-gated channels open and Na+ rushes into the cell. (B)</p> Signup and view all the answers

What is the primary consequence of hyperpolarization following repolarization in a neuron?

<p>It prevents the neuron from receiving another stimulus or raises the threshold for another stimulus. (C)</p> Signup and view all the answers

If the soma of a neuron remains intact after axonal damage, what potential outcome is possible?

<p>Axonal regeneration and eventual functional recovery, given the right conditions. (C)</p> Signup and view all the answers

What is the key feature that distinguishes the absolute refractory period from the relative refractory period?

<p>During the absolute refractory period, a neuron cannot respond to any stimulus. (D)</p> Signup and view all the answers

Which of the following is a primary function of organelles within a nerve cell?

<p>Manufacturing neurotransmitters and neuromodulators. (A)</p> Signup and view all the answers

Why does a larger axon diameter increase conduction velocity?

<p>It reduces internal resistance to ion flow. (D)</p> Signup and view all the answers

What is the primary function of myelin in neuronal conduction?

<p>To increase speed of action potential propagation. (A)</p> Signup and view all the answers

What is the primary role of microtubules and neurofilaments within a neuron?

<p>Forming the cytoskeleton and facilitating axoplasmic transport (B)</p> Signup and view all the answers

What is the key difference between anterograde and retrograde axoplasmic transport?

<p>Anterograde transport moves substances toward the axon terminal, while retrograde transport moves them toward the soma. (D)</p> Signup and view all the answers

What is the characteristic of saltatory conduction?

<p>Action potentials jump between Nodes of Ranvier. (B)</p> Signup and view all the answers

What primarily determines the size of postsynaptic potentials (PSPs)?

<p>The amount of neurotransmitter released and the number of open ion channels (A)</p> Signup and view all the answers

What is the crucial function of astrocytes in the nervous system?

<p>Maintaining nerve signals, protecting the blood-brain barrier, and secreting neurotrophic growth factors (B)</p> Signup and view all the answers

What are glial scars and how are they related to astrocytes?

<p>A type of scar tissue formed by astrocytes in response to damage where repair by the astrocyte is not possible (D)</p> Signup and view all the answers

What is the difference between temporal and spatial summation of EPSPs?

<p>Temporal summation involves rapid, successive firing of the same fiber, while spatial summation involves activation of multiple inputs simultaneously (B)</p> Signup and view all the answers

What is the primary function of oligodendrocytes in the central nervous system (CNS)?

<p>Forming and maintaining myelin sheaths around CNS axons (D)</p> Signup and view all the answers

What is convergence, regarding neuronal synaptic connections?

<p>A neuron receives input from many other neurons. (C)</p> Signup and view all the answers

What is the distinguishing feature regarding how oligodendrocytes myelinate axons?

<p>One oligodendrocyte can myelinate segments of multiple CNS axons. (D)</p> Signup and view all the answers

Which type of synapse involves a presynaptic terminal synapsing with the cell body of a postsynaptic neuron?

<p>Axosomatic (D)</p> Signup and view all the answers

What is the main function of Schwann cells in the peripheral nervous system (PNS)?

<p>Forming myelin sheaths around axons in the PNS (D)</p> Signup and view all the answers

Which of the following neurotransmitters is classified as inhibitory?

<p>Glycine (A)</p> Signup and view all the answers

What primary role do satellite cells play in the peripheral nervous system (PNS)?

<p>Surrounding cell bodies in PNS ganglia and playing a role in metabolism of ganglion cells. (D)</p> Signup and view all the answers

What differentiates a neurotransmitter from a neuromodulator?

<p>Neurotransmitters act on adjacent neurons, while neuromodulators can affect many neurons broadly. (B)</p> Signup and view all the answers

What is the primary function of ionotropic receptors?

<p>To directly allow the passage of ions across the cell membrane. (A)</p> Signup and view all the answers

What is the primary function of ependymal cells?

<p>Lining the central canal of the spinal cord and ventricles. (C)</p> Signup and view all the answers

Which statement best characterizes the function of microglia in the central nervous system (CNS)?

<p>They provide defense against infection, clean up debris, and act as the CNS immune system. (D)</p> Signup and view all the answers

In the context of cell membrane physiology, what is the function of non-gated ion channels?

<p>They are always open, allowing diffusion of a small number of ions for the resting membrane state. (B)</p> Signup and view all the answers

How does the sodium-potassium ($Na^+/K^+$) pump contribute to maintaining the resting membrane potential?

<p>By actively transporting 3 $Na^+$ ions out of the cell and 2 $K^+$ ions into the cell. (A)</p> Signup and view all the answers

What is a key characteristic of a receptor (generator) potential that distinguishes it from an action potential?

<p>It is a local, graded potential that decays with distance. (B)</p> Signup and view all the answers

What directly mobilizes vesicles in the chemical synaptic transmission process, leading to the release of neurotransmitters?

<p>Influx of $Ca^{2+}$ ions through voltage-gated channels. (C)</p> Signup and view all the answers

What is the primary role of acetylcholinesterase in synaptic transmission?

<p>Breaking down acetylcholine into inactive components. (D)</p> Signup and view all the answers

Which of the following accurately describes the function of G proteins in metabotropic neurotransmission?

<p>Activating effector proteins that initiate secondary messenger cascades. (A)</p> Signup and view all the answers

What is the most significant difference between ionotropic and metabotropic receptor actions?

<p>Ionotropic receptors directly open ion channels; metabotropic receptors act indirectly via second messengers. (A)</p> Signup and view all the answers

What is the primary function of synaptic vesicles in neurotransmission?

<p>Storing and protecting neurotransmitters from enzymatic breakdown. (A)</p> Signup and view all the answers

What is a notable characteristic of primary afferent neurons in the somatosensory system?

<p>They have a peripheral process that extends to receptors and a central process that enters the CNS. (C)</p> Signup and view all the answers

Which of the following is an example of an interoceptor?

<p>A receptor in the wall of the digestive tract that responds to pressure. (B)</p> Signup and view all the answers

In Myasthenia Gravis, which component of the neuromuscular junction is primarily affected by the autoimmune response?

<p>Acetylcholine receptors on the muscle cells. (B)</p> Signup and view all the answers

What distinguishes an agonist from an antagonist in the context of neurotransmitter action?

<p>An agonist promotes the effects of a neurotransmitter, while an antagonist impedes those effects. (B)</p> Signup and view all the answers

What is the role of prethalamic relay neurons in the somatosensory pathway?

<p>To synapse with primary afferent neurons and decussate before projecting to the thalamus. (C)</p> Signup and view all the answers

Which of the following somatosensory receptors is NOT an encapsulated receptor?

<p>Nociceptors. (B)</p> Signup and view all the answers

What is the primary function of the Thalamocortical projection fibers?

<p>Relay ascending sensory information from the thalamus to the cerebral cortex. (B)</p> Signup and view all the answers

What is the typical method of inactivation for GABA, Glutamate, and Glycine neurotransmitters in the synaptic cleft?

<p>Reuptake by the presynaptic terminal. (A)</p> Signup and view all the answers

How does the somatosensory system transmit information about the external environment to the brain?

<p>By converting environmental energy into electrical signals via receptors. (A)</p> Signup and view all the answers

Which type of somatosensation involves an inner joint sense, providing awareness of body position in space?

<p>Proprioception. (C)</p> Signup and view all the answers

Which of the following is a mechanism by which long-term potentiation (LTP) strengthens synaptic connections?

<p>Conversion of silent synapses into active synapses. (A)</p> Signup and view all the answers

What is the primary effect of long-term depression (LTD) on the postsynaptic membrane?

<p>Decreased likelihood of depolarization following glutamate release. (A)</p> Signup and view all the answers

What role does Brain-Derived Neurotrophic Factor (BDNF) play in neural plasticity?

<p>Supporting the survival of existing neurons and encouraging the growth of new neurons and synapses. (C)</p> Signup and view all the answers

What characterizes experience-expectant plasticity?

<p>Changes in the organization of the CNS during development. (B)</p> Signup and view all the answers

How does suturing an eye during the critical period for vision affect the development of ocular dominance columns?

<p>The ocular dominance columns develop a response to the non-sutured eye. (B)</p> Signup and view all the answers

What outcome is most likely when intervention with cochlear implants is delayed beyond the critical period for hearing?

<p>More limited development of the auditory cortex and hearing. (A)</p> Signup and view all the answers

What occurs in cortical map plasticity when a digit is removed, based on animal experimentation?

<p>The cortical areas redistribute, and areas adjacent to the removed digit expand. (C)</p> Signup and view all the answers

Following a stroke, reorganization during recovery is usually?

<p>Within the affected system. (B)</p> Signup and view all the answers

What has been the observed influence of exercise on BDNF in animal models?

<p>Exercise increases BDNF mRNA and protein levels in areas such as the cerebral cortex, cerebellum, and spinal cord. (C)</p> Signup and view all the answers

What is the function of constraint-induced movement therapy (CIMT)?

<p>Restraining the unaffected extremity to force use of the affected extremity. (B)</p> Signup and view all the answers

What is the primary purpose of sensory exams in neurological testing?

<p>To establish the presence, location, type, and severity of sensory impairment. (C)</p> Signup and view all the answers

In sensory testing, what does 'distal to proximal' refer to?

<p>Testing sensation from the ends of the limbs towards the torso. (B)</p> Signup and view all the answers

Which of the following factors would LEAST likely influence the accuracy of sensory testing?

<p>Ambient room temperature. (C)</p> Signup and view all the answers

Why is it important to explain the sensory testing procedure to the patient with their eyes open before occluding their vision?

<p>To allow the patient to understand what the stimulus feels like on an area of presumed intact sensation. (B)</p> Signup and view all the answers

Which of the following sensory modalities is tested using test tubes with cold and hot water?

<p>Temperature (D)</p> Signup and view all the answers

When testing light touch and tactile localization, what should the patient be asked to do while their eyes are closed?

<p>Describe or point to where they feel the touch. (C)</p> Signup and view all the answers

When assessing sharp/dull sensation, why is it important to introduce the stimuli to an unaffected area first?

<p>To establish a baseline and ensure the patient understands the difference between sharp and dull. (C)</p> Signup and view all the answers

In conscious proprioception testing, how should the segment of the body being tested be held?

<p>At a right angle to the intended direction of movement. (B)</p> Signup and view all the answers

Which of the following best describes the concept of neural plasticity?

<p>The ability of the nervous system to change its structure, function, or chemical profiles. (D)</p> Signup and view all the answers

What is the primary distinction between 'recovery' and 'compensation' in the context of neurological rehabilitation?

<p>Recovery involves restoration of damaged functions, while compensation uses unaffected systems to perform tasks. (A)</p> Signup and view all the answers

What cellular process is MOST closely associated with experience-dependent plasticity?

<p>Increases or decreases in the number of synapses. (B)</p> Signup and view all the answers

What cellular process is essential for long-lasting changes in the strength of synapses and is heavily involved in learning and memory?

<p>Long-term potentiation (LTP) (C)</p> Signup and view all the answers

Which of the following changes are required for experience-dependent plasticity to occur?

<p>Synthesis of new proteins, growth of new synapses, and modifications of existing synapses. (A)</p> Signup and view all the answers

While documenting sensory testing results, listing intact, decreased/impaired, exaggerated, inaccurate, absent, and inconsistent options best reflects which aspect of the results?

<p>Grading (A)</p> Signup and view all the answers

Which condition is LEAST likely to be associated with changes in sensory integrity?

<p>Upper respiratory infection (B)</p> Signup and view all the answers

What distinguishes rapidly adapting (phasic) receptors from slowly adapting (tonic) receptors?

<p>Rapidly adapting receptors stop firing quickly after the stimulus is removed. (C)</p> Signup and view all the answers

Which of the following is a function of proprioceptors?

<p>Sense static muscle length and limb movement. (C)</p> Signup and view all the answers

What type of sensory receptors are responsible for detecting tissue-damaging stimuli?

<p>Nociceptors (A)</p> Signup and view all the answers

Which sensory pathway is responsible for transmitting discriminative tactile sensations to the cerebral cortex?

<p>Dorsal Column-Medial Lemniscus system (DCML) (D)</p> Signup and view all the answers

Where do the primary afferent neurons receive their stimulation?

<p>From the stimulus at the receptor field. (B)</p> Signup and view all the answers

What characteristic of cutaneous receptor fields is true regarding their size and density?

<p>Receptive fields are smaller distally than proximally. (B)</p> Signup and view all the answers

Which type of sensory axon fiber has the slowest conduction velocity?

<p>C (A)</p> Signup and view all the answers

How does a generator potential affect neuronal signaling?

<p>It generates an electrical impulse only if it reaches a certain threshold. (C)</p> Signup and view all the answers

What is the role of joint mechanoreceptors?

<p>Respond to mechanical deformation in joint capsules and ligaments. (B)</p> Signup and view all the answers

What distinguishes the dorsal column-medial lemniscus system from the spinothalamic tract?

<p>The pathways differ in types of sensations carried and point of crossing. (B)</p> Signup and view all the answers

Which of the following describes axons crossing the midline to connect equivalent areas of the central nervous system?

<p>Commissures (A)</p> Signup and view all the answers

Which cerebral lobe is primarily responsible for processing visual information?

<p>Occipital lobe (B)</p> Signup and view all the answers

What is the primary function of the thalamus?

<p>Relaying sensory and motor information to the cortex (A)</p> Signup and view all the answers

The arcuate fasciculus connects which two key language areas?

<p>Broca's area and Wernicke's area (C)</p> Signup and view all the answers

Which structure plays a crucial role in maintaining homeostasis and regulating functions such as temperature, hunger, and thirst?

<p>Hypothalamus (C)</p> Signup and view all the answers

What type of fibers connect different regions within the same cerebral hemisphere?

<p>Association fibers (D)</p> Signup and view all the answers

Which subcortical structure is associated with the regulation of muscle movement and is affected in Parkinson's disease?

<p>Basal Ganglia (B)</p> Signup and view all the answers

Where is the pineal gland located, and what is its primary function?

<p>Epithalamus; circadian rhythms (A)</p> Signup and view all the answers

What is the main function of the cerebellum?

<p>Coordination and motor learning (A)</p> Signup and view all the answers

Which of the following regions contains the primary motor cortex?

<p>Precentral gyrus (B)</p> Signup and view all the answers

Damage to the brainstem is most likely to affect what?

<p>Vital functions (D)</p> Signup and view all the answers

What is the role of the primary somatosensory area?

<p>Processes any sensory signal (C)</p> Signup and view all the answers

What separates the frontal and parietal lobes from the temporal lobe?

<p>Lateral fissure/sulcus (D)</p> Signup and view all the answers

What pathway links superior and inferior regions of the CNS?

<p>Projection pathways (C)</p> Signup and view all the answers

Which best describes the sensory functions of the cerebellum?

<p>Unconscious proprioception (D)</p> Signup and view all the answers

What is the primary role of the DCML pathway in somatosensory processing?

<p>Processing discriminative touch and proprioception (A)</p> Signup and view all the answers

Which component is responsible for 'fast' nociception in the anterolateral system?

<p>A-delta fibers (C)</p> Signup and view all the answers

What happens to sensory signals in spinal cord lesions such as Brown-Sequard syndrome?

<p>Contralateral loss of pain and temperature, ipsilateral loss of touch and proprioception (C)</p> Signup and view all the answers

In which part of the nervous system do the primary free nerve endings primarily reside?

<p>Peripheral nervous system (A)</p> Signup and view all the answers

What sensory modalities are affected by a posterior column lesion?

<p>Discriminative touch and vibration (B)</p> Signup and view all the answers

What is the effect of demyelination in the context of peripheral nerve function?

<p>Severe effects on proprioception and vibratory sense (D)</p> Signup and view all the answers

Which part of the thalamus is responsible for processing somatosensation from the face?

<p>Ventral posteromedial Thalamus (VPM) (C)</p> Signup and view all the answers

What is the primary role of the spinocerebellar tracts?

<p>Relay of touch and pressure information for movement correction (C)</p> Signup and view all the answers

How does acute pain differ from chronic pain?

<p>Chronic pain may occur without tissue damage (B)</p> Signup and view all the answers

Which sensory pathway is primarily responsible for the transmission of light touch sensations?

<p>DCML pathway (A)</p> Signup and view all the answers

Which of the following describes the fast conduction mechanism in nociception?

<p>Fast conduction is mediated by myelinated A-delta fibers (A)</p> Signup and view all the answers

What best describes the role of the paralleled ascending system?

<p>Carries sensory information related to autonomic functions (D)</p> Signup and view all the answers

What type of sensory fibers primarily sense temperature and crude touch?

<p>A-delta fibers (A), C fibers (C)</p> Signup and view all the answers

What neurological condition is associated with the varicella-zoster virus affecting the sensory nerve roots?

<p>Shingles (A)</p> Signup and view all the answers

What is the primary difference between acute pain and chronic pain?

<p>Acute pain serves a protective function, while chronic pain does not. (A)</p> Signup and view all the answers

Which of the following accurately describes nociception?

<p>Nociception can occur independently of pain perception. (B)</p> Signup and view all the answers

What role does substance P play in pain modulation?

<p>It enhances the nociceptive signal. (A)</p> Signup and view all the answers

What is the purpose of the gate-control theory of pain?

<p>To illustrate how non-painful stimuli can inhibit painful sensations. (D)</p> Signup and view all the answers

Chronic pain is characterized by which of the following?

<p>A hypersensitive nervous system that amplifies pain signals. (C)</p> Signup and view all the answers

In which situation can referred pain occur?

<p>When the pain is perceived in a body part different from its site of origin. (B)</p> Signup and view all the answers

What is the significance of pain assessment in clinical practice?

<p>It is primarily based on patient self-report to gauge pain intensity. (B)</p> Signup and view all the answers

Which system in the body is responsible for the antinociceptive effects?

<p>Endorphins act to suppress pain sensation. (B)</p> Signup and view all the answers

What is a common cause of enhanced symptoms in fibromyalgia?

<p>Increased biological amplification of pain signals. (A)</p> Signup and view all the answers

What characteristic distinguishes fast nociception from slow nociception?

<p>Fast nociception is usually associated with low emotional impact. (A)</p> Signup and view all the answers

What happens to pain pathways in conditions of chronic pain?

<p>Atrophy of descending inhibition occurs in the brain. (A)</p> Signup and view all the answers

Which of the following is a symptom of altered sensory processing?

<p>Excessively heightened pain response to mild stimuli. (B)</p> Signup and view all the answers

What does chronic pain as a disease indicate?

<p>Pain modulation involves both inhibitory and excitatory pathways. (A)</p> Signup and view all the answers

How does acute pain typically serve the body?

<p>By warning of tissue damage or potential injury. (D)</p> Signup and view all the answers

Flashcards

Expressive Aphasia

A communication disorder with difficulty in word retrieval despite intact thought processes.

Broca's Area

A region in the frontal lobe responsible for speech production.

Brown-Sequard Syndrome

A condition from spinal cord injury affecting one side of the body.

Neuron

A nerve cell that transmits signals throughout the body.

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Neuroglia

Supporting cells in the nervous system that outnumber neurons.

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Presynaptic Neuron

The neuron that sends information in a synaptic transmission.

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Postsynaptic Neuron

The neuron that receives information from the presynaptic neuron.

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Central Nervous System (CNS)

Part of the nervous system consisting of the brain and spinal cord.

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Peripheral Nervous System (PNS)

Nerves outside the CNS, including cranial nerves except I and II.

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Somatic Nervous System

Controls voluntary muscles in the body.

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Autonomic Nervous System

Controls involuntary functions like smooth muscle and glands.

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Sympathetic Division

Part of the autonomic system; triggers fight or flight response.

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Parasympathetic Division

Part of the autonomic system; promotes rest and digest.

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Meninges

Protective membranes covering the brain and spinal cord.

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Gray Matter

Part of the CNS with neuronal cell bodies and dendrites.

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White Matter

Inner CNS composed of axons, includes myelin sheaths.

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Decussation

Crossing of axons from one CNS side to another.

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Commissure

Axons that cross from one side of the CNS to the other side.

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Afferent

Nerve signals traveling towards the brain/CNS, usually sensory information.

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Efferent

Nerve signals traveling away from the brain/CNS, mainly for voluntary movements.

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Gyri and Sulci

Bumps and grooves on the brain's surface, respectively.

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Frontal Lobe

Brain area responsible for planning, language expression, and speech.

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Parietal Lobe

Brain area that acts as the primary sensory region.

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Thalamus

Relay station for sensory and motor information to the cortex.

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Hypothalamus

Regulates homeostasis and visceral actions, connected to the endocrine system.

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Cerebellum

Part of the brain involved in coordination and balance; contains two hemispheres.

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Corpus Callosum

Major white matter tract connecting the two cerebral hemispheres.

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Primary Motor Area

Part of the cortex sending signals for voluntary movements.

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Brodmann’s Area

52 designated cortical locations mapped based on function and structure.

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Basal Ganglia

Nuclei deep within the brain regulating and controlling movements.

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Cerebral Cortex

Outermost layer of the brain handling higher order functions.

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Projection Fibers

Connect different areas of the brain and spinal cord; relays signals top down or bottom up.

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Focal Damage

Damage in one specific area of the nervous system.

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Multifocal Damage

Damage occurring in more than one area of the nervous system.

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Diffuse Damage

Widespread damage throughout the brain.

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Dura Mater

The tough, outermost layer of the meninges.

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Arachnoid Mater

The middle layer of the meninges, thin and avascular.

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Cerebrospinal Fluid (CSF)

Clear fluid that cushions and nourishes the brain.

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Hydrocephalus

Accumulation of CSF in the ventricles due to imbalance in production or absorption.

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Transient Ischemic Attack (TIA)

Brief loss of brain function with recovery within 24 hours.

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Cerebrovascular Accident (CVA)

Neurological deficit lasting over a day due to a vascular disorder.

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Circle of Willis

An anastomosis of arteries supplying blood to the brain.

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Blood-Brain Barrier

A selective barrier preventing pathogens from entering the CNS.

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Positron Emission Tomography (PET)

Imaging technique using radioactive material to visualize brain metabolic function.

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Aneurysm

Dilation of an artery wall, leading to a risk of rupture.

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Cerebral Arteries

Arteries supplying blood to different areas of the brain.

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Axonal Regeneration

The ability of a neuron to regenerate axons if the soma is intact.

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Axoplasmic Transport

The bidirectional movement of substances between the cell body and axon terminal.

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Astrocytes

Star-shaped neuroglial cells that maintain nerve signals and protect the blood-brain barrier.

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Oligodendrocytes

Neuroglial cells responsible for forming and maintaining myelin sheaths in the CNS.

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Schwann Cells

Neuroglia that form myelin sheaths around axons in the PNS.

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Blood-CSF Barrier

Barrier formed by ependymal cells that helps regulate the composition of cerebral spinal fluid.

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Microglia

Glial cells that act as the immune system of the CNS, cleaning up debris.

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Resting Membrane Potential

The electrical state of a neuron when not transmitting signals, typically -65mV.

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Depolarization

The process where the neuron becomes less negative inside, moving toward action potential.

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Hyperpolarization

When the inside of the neuron becomes more negative than the resting state.

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Magnetic Resonance Imaging (MRI)

A technique using a strong magnetic field to create detailed images of soft tissues in the body.

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Generator Potential

A local change in electrical potential that transduces environmental stimuli into information.

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Magnetic Resonance Angiography (MRA)

An imaging technique that visualizes blood vessels using a contrast medium.

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Blood Oxygen Level Dependent MRI (BOLD MRI)

A type of MRI that measures brain activity by detecting changes in oxygen consumption.

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Modality-Gated Channels

Ion channels that open in response to specific types of stimuli like pressure or chemicals.

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Diffusion Tensor Imaging (DTI)

An MRI technique that measures the diffusion of water in brain tissue to visualize white matter tracts.

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Ligand-Gated Channels

Channels that open when neurotransmitters bind to their receptors.

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Voltage-Gated Channels

Channels that open in response to changes in membrane potential due to electrical signals.

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Functional MRI (fMRI)

An MRI that tracks changes in blood flow to assess brain activity during specific tasks.

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Electroencephalography (EEG)

A non-imaging test that records electrical activity in the brain via scalp electrodes.

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Spinal Cord

The long bundle of nervous tissue extending from the medulla to the L1/L2 vertebra.

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Cervical Enlargement

The enlarged region of the spinal cord responsible for nerve supply to the upper limbs.

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Lumbar Enlargement

The section of the spinal cord that supplies nerves to the lower limbs.

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Conus Medullaris

The tapered end of the spinal cord, typically situated at L1-L2.

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Cauda Equina

A bundle of spinal nerves and roots at the lower end of the spinal cord, resembling a horse's tail.

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Dermatome

The area of skin innervated by sensory fibers from a single spinal nerve root.

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Myotome

The set of muscles innervated by motor fibers from a single spinal nerve root.

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Segmental vs. Vertical Organization

Segmental relates to spinal nerves; vertical pertains to pathways ascending and descending in the spinal cord.

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Gray Matter vs. White Matter

Gray matter contains neuronal cell bodies; white matter contains myelinated axons for communication.

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Slowly Adapting Receptors

Receptors that continue firing as long as a stimulus is present; includes proprioceptors.

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Rapidly Adapting Receptors

Receptors that stop firing quickly after the stimulus is applied or withdrawn; includes Pacinian corpuscles.

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Mechanoreceptors

Receptors that respond to mechanical deformation, such as touch and pressure.

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Nociceptors

Receptors that respond to tissue-damaging stimuli, typically interpreted as pain.

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Proprioceptors

Sensory receptors located in muscles and tendons that detect body position and movement.

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Muscle Spindles

Type of proprioceptor sensitive to stretching and lengthening of muscles.

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Golgi Tendon Organs

Proprioceptors located at the junction of muscle and tendon; sensitive to muscle tension.

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Dorsal Column-Medial Lemniscus System

Pathway for carrying tactile sensation and proprioception from receptors to the cerebral cortex.

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Spinothalamic Tract

Pathway for carrying nociceptive and temperature information to the brain.

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Afferent Nerves

Nerve fibers that carry sensory information to the CNS from receptors.

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Local Potentials

Initial change in membrane potential; first step in transmission.

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Excitatory Potential

Increases the likelihood of generating an action potential.

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Inhibitory Potential

Decreases the likelihood of generating an action potential.

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Summation

The process of integrating multiple potentials.

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Threshold

The level of excitability needed to fire an impulse.

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Action Potential

A rapid change in membrane potential that occurs if threshold is reached.

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Saltatory Conduction

The process of action potentials jumping from node to node in myelinated axons.

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Excitatory Post Synaptic Potentials (EPSPs)

Local depolarization in the postsynaptic neuron caused by excitatory neurotransmitters.

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Inhibitory Post Synaptic Potentials (IPSPs)

Local hyperpolarization in the postsynaptic neuron due to inhibitory neurotransmitters.

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Spatial Summation

Simultaneous activation of multiple presynaptic inputs at different locations.

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Neurotransmitters

Chemicals released from the presynaptic neuron into the synaptic cleft to affect postsynaptic neurons.

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Neuromodulators

Substances that modulate the activity of neurotransmitters, affecting many neurons.

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Pain as Brain Output

Pain is always generated by the brain, regardless of injury.

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Pain vs Tissue Damage

Pain does not equal the amount of tissue damage present.

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Factors Influencing Pain

Pain is affected by factors like mood, stress, and sleep.

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Acute Pain Function

Acute pain serves as a warning for potential harm or injury.

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Chronic Pain Mechanism

Chronic pain results from a hypersensitive nervous system and is not a danger signal.

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Nociception

Nociception is the sensory process that detects harmful stimuli.

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Fast Nociception

Fast nociception is sharp and well-localized, enduring briefly.

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Slow Nociception

Slow nociception is dull, persistent, and often accompanied by suffering.

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Gate-Control Theory

Pain can be modulated by stimulating other sensory pathways to 'close the gate' on pain signals.

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Substance P

Substance P is a neuropeptide involved in transmitting pain signals.

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Antinociceptive Systems

These are systems that suppress pain in response to otherwise painful stimuli.

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Excitatory Neurotransmitter

A neurotransmitter that increases the likelihood of a neuron firing.

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Inhibitory Neurotransmitter

A neurotransmitter that decreases the likelihood of a neuron firing.

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Referred Pain

Referred pain is perceived at a location different from the source of pain.

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Allodynia

Allodynia is when pain occurs from stimuli that normally do not provoke pain.

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Metabotropic Receptors

Receptors that activate ion channels indirectly via G proteins.

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G Protein Coupled Receptor

A receptor type that can be excitatory or inhibitory, involved in slow signaling.

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Fibromyalgia

Fibromyalgia is a condition characterized by widespread pain and sensitivity, often linked to altered pain processing.

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Chemical Synaptic Transmission

Process by which neurotransmitters are released and activate receptors.

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Pain Assessment

The most reliable indicator of pain intensity is the patient's self-report, using various scales.

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Neurotransmitter Synthesis

The creation of neurotransmitters from precursors and enzymes.

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Exocytosis

Process of neurotransmitter release from vesicles into the synaptic cleft.

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Reuptake Mechanism

The process where neurotransmitters are absorbed back into the presynaptic neuron.

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Myasthenia Gravis

An autoimmune disorder affecting communication between nerves and muscles.

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Agonist

A substance that promotes or mimics the action of a neurotransmitter.

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Antagonist

A substance that blocks or impedes the action of a neurotransmitter.

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Somatosensation

The collection of sensations including touch, temperature, and pain.

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Proprioception

The body's ability to sense its position and movement.

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Long-Term Potentiation (LTP)

A lasting enhancement in synaptic strength following high-frequency stimulation.

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Long-Term Depression (LTD)

A lasting reduction in synaptic strength due to low-frequency stimulation or inactivity.

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BDNF

Brain-derived neurotrophic factor; a protein that supports neuron survival and growth.

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Experience-Expectant Plasticity

Changes in brain organization during development based on experiences.

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Critical Period

A specific time frame during which certain experiences must occur for proper development.

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Cochlear Implants

Devices that stimulate the auditory nerve to help individuals with hearing loss.

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Cortical Map Plasticity

The brain's ability to reorganize itself based on changes in sensory input or injury.

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Synaptogenesis

The formation of new synapses, critical for learning and recovery.

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Habituation

The decrease in response to a repeated benign stimulus over time.

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Constraint-Induced Movement Therapy (CIMT)

A rehabilitation technique that forces use of an affected limb by restraining the unaffected one.

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Somatosensory Pathways

Afferent pathways for sensory information from the periphery to the cortex.

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DCML Pathway

Pathway responsible for discriminative touch, vibration, and proprioception.

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Types of Nociceptors

Four types: mechanical, thermal, chemically sensitive, polymodal.

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Cerebellum Function

Compares intended movements to actual movements for coordination.

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Peripheral Nerve Lesion

Pathology affecting one or more peripheral nerves leading to sensory loss.

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Spinal Cord Injury

Damage to the spinal cord affecting neural functions depending on the site.

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Chronic Pain

Pain lasting longer than expected for healing, may have no protective function.

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Acute Pain

Sudden pain with a clear cause, often protective in nature.

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Hemisected Spinal Cord

Condition causing motor and sensory loss on one side, affecting pain locally.

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Thalamus Role

Relay station for sensory and motor information processed for the cortex.

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Nociceptive vs. Neuropathic Pain

Nociceptive pain is due to injury, while neuropathic pain comes from nervous system malfunction.

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Pain Processing Pathways

Nociception pathways including neospinothalamic and paleospinothalamic systems.

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Rexed’s Laminae

A classification system dividing spinal gray matter into 10 histological regions based on structure and function.

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Cranial Nerve V

The trigeminal nerve, responsible for sensation in the face and motor functions such as biting and chewing.

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Pyramidal Decussation

The crossing of motor fibers in the medulla, leading to contralateral control of the body.

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Reticular Formation (RF)

A network of neurons in the brainstem crucial for arousal, consciousness, and autonomic functions.

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Ascending Reticular Activating System (ARAS)

Part of the RF that helps regulate levels of consciousness from alertness to coma.

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Unipolar Neurons

Neurons with a single process extending from the soma, primarily found in sensory spinal nerves.

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Dendrites

Branch-like extensions of a neuron that receive signals from other neurons.

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Axon Hillock

The junction between the soma and the axon where action potentials are generated.

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Complete Sensory Evaluation

A thorough testing process to assess sensory function.

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Differential Diagnosis

Process of distinguishing one condition from another based on testing and history.

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Conscious Relay Pathways

Pathways that convey sensory information to the brain, including touch and proprioception.

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Sensory Testing Guidelines

Procedures that ensure accuracy and reliability during sensory evaluations.

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Nociception Testing

Assessing the ability to detect sharp and dull stimuli.

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Temperature Sensation Testing

Evaluation of the ability to sense hot and cold stimuli.

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Neural Plasticity

The brain's ability to change functions and structure based on experiences.

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Recovery vs. Compensation

Recovery is restoring damaged functions; compensation is using unaffected systems.

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Experience-Dependent Plasticity

Brain changes driven by learning and experiences, affecting synaptic strength.

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Cutaneous Sensations

Sensations detected through the skin, including touch and pain.

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Sharp/Dull Discrimination

Assessing the ability to differentiate between sharp and dull stimuli.

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Sensory Pathways Overview

Two main pathways for sensory information: DCML and Spinothalamic.

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Grading Sensory Response

Evaluation of sensory responses as normal, impaired, or absent.

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Study Notes

Overview of the Nervous System

  • The nervous system is broadly divided into the Central Nervous System (CNS) and the Peripheral Nervous System (PNS).
  • The CNS is encased by bone (skull and vertebrae); anything outside is the PNS (except the cauda equina).
  • Cranial nerves I and II remain within the cranium; cranial nerves III-XII exit the skull.
  • The somatic nervous system controls voluntary muscles, while the autonomic nervous system controls involuntary actions (smooth muscle, cardiac muscle, glands).
  • Autonomic system has sympathetic (fight-or-flight) and parasympathetic (rest-and-digest) divisions.

Cells of the Nervous System

  • Neurons (nerve cells) have a soma (cell body), axons, and dendrites.
  • Neuroglia (supporting cells) outnumber neurons. Macroglia (astrocytes, oligodendrocytes, Schwann cells) and microglia support neurons.
  • Ependymal cells line the brain's ventricles.
  • Synapses are the gaps between neurons where neurotransmitters are released.

Communication between Neurons

  • Presynaptic neurons transmit information; postsynaptic neurons receive it.
  • Action potentials (nerve impulses) travel from cell to cell.

Cranial Nerves

  • Cranial nerves III-XII exit the skull to innervate facial, head, and neck areas.

Basic Design of the Adult Nervous System

  • Contains the central nervous system (CNS) & peripheral system (PNS) in addition to cell types (neurons & neuroglia).

Brain Regions

  • Cerebrum: Hemispheres and basal ganglia, important for higher-order functions.
  • Diencephalon: Thalamus and hypothalamus, relay and homeostasis.
  • Cerebellum: Balance and coordination.
  • Brainstem: Midbrain, pons, medulla; vital functions and cranial nerve origination.

Spinal Region

  • Spinal cord (foramen magnum to L1/L2): Conus medullaris and cauda equina.
  • Roots and rootlets (dorsal sensory and ventral motor).
  • Spinal nerves: Paired nerves at 31 segments.
  • Meninges: Protective coverings (dura mater, arachnoid mater, pia mater).

Cerebrospinal Fluid (CSF)

  • CSF circulates in and around brain and spinal cord providing cushioning, nutrient delivery, and waste removal.

Meninges and CSF Clinical Application

  • Meningitis: Inflammation of the meninges
    • Symptoms include headache, fever, confusion, vomiting, and stiff neck.

White and Gray Matter

  • Gray matter: Cell bodies and dendrites (outer cortex and basal ganglia).
  • White matter: Axons (inner portion of brain), myelin insulates axons

Definitions

  • Tracts: Bundles of axons with the same origin, termination, and function.
  • Decussation: Axon crossing the midline.
  • Commissure: Axon crossing to the equivalent area on the opposite side.
  • Afferent: Towards CNS (sensory).
  • Efferent: Away from CNS (motor).
  • The terms Tract, Pathway, Lemniscus, Fasciculus, Column, Peduncle, Capsule are all bundles of axons.

Major Regions of the CNS

  • The cerebrum, diencephalon, cerebellum, and brainstem

Cerebral Structures

  • Cerebral cortex: Outermost layer of the brain (gray matter)
  • Subcortical structures: Internal capsule, basal ganglia, limbic system (white matter).

Cerebellum Function

  • Coordination, regulation, and modulation of motor behavior

Brainstem Functions

  • Vital functions (cardiovascular activity and respiration), conveys information from the cerebrum and spinal cord through tracts, consciousness, and cranial nerve nuclei origination.

CNS Support Systems: Meninges, Cerebrospinal Fluid, Vascular Supply

  • Meninges: Cover the brain in layers providing protection (dura mater, arachnoid mater, pia mater)
  • Cerebrospinal fluid: Circulates in and around the CNS.
  • Vascular Supply: Brain, spinal cord, and nerves depend on continuous blood supply.

Vascular Supply

  • Internal carotid arteries: Supply anterior, superior, and lateral cerebral hemispheres.
  • Vertebral arteries: Supply the brainstem, cerebellum, and posteroinferior cerebrum.
  • Circle of Willis: Anastomosis of arteries providing alternate blood supply to brain.

Disorders of Vascular Supply

  • Transient ischemic attack (TIA): Brief loss of function with full recovery.
  • Cerebrovascular accident (CVA): Persistent neurological deficit.
  • Infarction: Vessel occlusion (stroke).
  • Hemorrhage: Rupture of blood vessel causing bleeding into the brain.
  • Arteriovenous malformation (AVM): Abnormal connection between arteries and veins in brain.
  • Aneurysm: Dilation of an artery or vein.

CNS Imaging Techniques

  • PET: Measures metabolic activity, blood flow
  • CT: Shows bone and tissue
  • MRI: Shows soft tissue structures in detail
  • MRA: Shows blood vessels in detail
  • BOLD MRI: Shows oxygen levels in blood to assess brain function
  • DTI: Shows white matter tracts, good for ischemic stroke assessment.
  • EEG: Measures brain electrical activity

Anatomy and Organization of the Spinal Cord and Brainstem

  • Spinal cord, from foramen magnum to L1-L2, ends in conus medullaris and cauda equina.
  • Cervical and lumbar enlargements for UE and LE innervation.
  • Spinal cord segments are divided into cervical (8), thoracic (12), lumbar (5), sacral (5), coccygeal (1) sections.

Spinal Cord: Internal Organization

  • Gray matter ("H" shape), white matter (surrounds gray).
  • Levels of gray matter vary based on peripheral innervation density.

Fiber Tracts of the Spinal Cord

  • Ascending and descending tracts (dorsal columns, spinothalamic, spinocerebellar, corticospinal)

Levels vs. Tracts

  • Segmental: Specific spinal level innervation.
  • Vertical/tracts: Long, ascending, and descending pathways.

Brainstem: Surface Features and Internal Organization

  • Cranial nerves attached to the brainstem (midbrain, pons, medulla oblongata) and reticular formation (RF): Arousal, motor function, autonomic activity, and pain modulation

Nervous System Cells and Communication

  • Neurons (excitable cells) and Neuroglia (supporting cells) are important elements in transmitting and supporting nervous system activity.
  • Neuron structure and function is critical for neural communication; they include axons, dendrites, and cell bodies.
  • Different types of channels are crucial and include gated channels and pump proteins.
  • The neuroglia are essential for maintaining the correct environment for the neurons to function properly. These include astrocytes, oligodendrocytes, Schwann cells, satellite cells, and ependymal cells & microglia.

Neurotransmission

  • Neurotransmitters and neuromodulators are chemicals that neurons use to communicate with each other and have different effects.
  • The process occurs in steps including synthesis, packaging, release into synapse, receptor interaction, and inactivation of neurotransmitter.

Somatosensory System: Reception to Perception

  • Different types of receptors exist that transform physical stimuli and information into action potentials.
  • Somatosensation involves receptors, primary afferent neurons, prethalamic neurons, decussation, thalamic neurons, and the cerebral cortex.

Specific Types of Receptors

  • Different types of receptors exist that are described by their structure, stimulus source, adaptation rate, and type of stimulus.

Primary Afferents and Their Receptors

  • Afferent information is carried by different types of nerve fibers (e.g. A-alpha, A-beta) which can transmit different levels of sensation with varying conduction speeds.

Conscious Relay Pathways

  • Somatic sensation pathways (ex: dorsal column-medial lemniscus system, spinothalamic tract).
  • Specific nerve tracts conduct various types of somatic sensations to the brain via the anterolateral pathway or the dorsal column.

Nociception and Pain

  • Nociceptors detect noxious stimuli (potentially damaging), and pain is the associated brain experience.
  • Nociception pathways (lateral & paramedial) transmit different types of nociceptive information to the brain.

Pain Modulation

  • The brain has mechanisms to modulate pain (e.g., gate control theory and antinociceptive systems).
    • Descending inhibitory circuits in the brain either diminish or amplify pain messages.

Altered Sensory Symptoms

  • Paresthesia (tingling) and dysesthesia (unpleasant sensation), allodynia (pain from normally painless stimuli), and hyperalgesia (excessive pain) result from altered sensory processing.

Pain Assessment

  • Patients should be assessed in a comprehensive manner including history, localization, severity and other relevant factors. The patient’s subjective pain report is the most reliable measure of pain.

Clinical Somatosensory Screening and Testing

  • Sensory examination is part of a neurological evaluation.
  • Screening and comprehensive testing vary based on patient history and suspected pathology.
  • Various tests are used to assess light touch, sharp/dull, temperature, pain, pressure, proprioception, and vibration.

Neural Plasticity of the Nervous System

  • The nervous system can change its functions, chemical profiles, and structures.
  • Plasticity is critical for the recovery and rehabilitation of nervous system injuries.
  • Various methods of neural change both during development and as a result of injury/use.

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