Physio V 2 hard

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Questions and Answers

What happens to the external intercostal muscles when there is damage below the C5 segment?

They function normally due to diaphragm compensation.

They stop functioning due to loss of impulses. (correct)

They become overactive without control.

They continue to receive impulses from the brain.

If a person experiences spinal cord transection above C5, what is the immediate outcome on respiration?

No respiratory muscles receive impulses. (correct)

Breathing becomes more efficient.

The person can still breathe with external assistance.

Only the diaphragm continues to function.

What is the risk if artificial respiration is not initiated within five minutes following severe spinal cord injury?

Temporary breathing difficulties.

Loss of ability to feel pain.

Irreversible brain neuron death begins. (correct)

Increased muscle control in the trunk.

Which scenario is most likely to result in damage above the C5 segment?

Traffic accidents causing neck fractures. Signup and view all the answers

What is a primary consequence of spinal shock immediately following a spinal cord injury?

Full depression of spinal cord functions. Signup and view all the answers

Why is the diaphragm still able to receive impulses despite damage below C5?

It is controlled by motor neurons above C5. Signup and view all the answers

What occurs if a person survives severe spinal cord injury while lacking the ability to ventilate lungs?

They require lifelong mechanical ventilation. Signup and view all the answers

What is the primary function of ascending sensory pathways?

They carry information from peripheral receptors to the brain. Signup and view all the answers

Following damage above C5, which respiratory muscle is predominantly impacted?

Intercostal muscles. Signup and view all the answers

Which statement accurately describes the pyramidal pathway?

It begins in the primary motor area of the cerebral cortex. Signup and view all the answers

What triggers phasic stretch reflexes?

Rapid stretching of skeletal muscle. Signup and view all the answers

What is the main role of the Golgi tendon organ in reflex functions?

To sense muscle stretch and cause muscle relaxation under excessive load. Signup and view all the answers

Which reflex is primarily responsible for supporting the body when standing up?

Positive support reaction Signup and view all the answers

What defines the function of the crossed extensor reflex?

It allows for the support of body weight by the opposite limb during pain stimuli. Signup and view all the answers

Which pathway is primarily responsible for adjusting and regulating movement?

Extrapyramidal pathways Signup and view all the answers

Which reflex is characterized by its initiation via nociceptive stimuli?

Flexor reflex Signup and view all the answers

How are rhythmic reflexes defined in terms of muscle activity?

They cause alternating activation and inhibition of muscle function. Signup and view all the answers

What is the consequence of a transection above the cervical 5th segment?

Death is the most common outcome Signup and view all the answers

Which areas of the spinal cord are primarily responsible for parasympathetic reflexes?

S2-S4 segments Signup and view all the answers

Which of the following statements is true regarding spinal shock?

It is an immediate outcome following high spinal cord transection. Signup and view all the answers

What percentage of lung ventilation is provided by the diaphragm?

75% Signup and view all the answers

Which spinal cord segments are responsible for innervating the diaphragm?

C3-C4 Signup and view all the answers

What is the role of the medullary respiratory center?

It sends impulses to activate the phrenic nerve. Signup and view all the answers

Which condition is a main contributor to the occurrence of spinal shock?

High spinal cord transection Signup and view all the answers

What role do T segments in the spinal cord play?

They innervate external intercostal muscles in coordination with rib spaces. Signup and view all the answers

What is the primary role of the highest autonomic center in the hypothalamus?

Coordinates sympathetic and parasympathetic nervous system activity Signup and view all the answers

Which hypothalamic structure is primarily responsible for hunger regulation?

Lateral hypothalamic area Signup and view all the answers

Which function is associated with the anterior hypothalamus?

Regulating responses to heat Signup and view all the answers

How does the hypothalamus regulate sleep behavior?

Through the activity of the suprachiasmatic nuclei concerning light cycles Signup and view all the answers

What is a function of the ventromedial nucleus of the hypothalamus?

Decreases food intake Signup and view all the answers

Which area of the hypothalamus is involved in thermoregulation?

Posterior hypothalamus Signup and view all the answers

Which functions are regulated by the neuroendocrine cells in the medial and lateral pre-optic nuclei?

Sexual functions and lactation Signup and view all the answers

Which hypothalamic structure helps regulate circadian rhythms?

Suprachiasmatic nucleus Signup and view all the answers

What is the consequence of damage to the cerebellum related to eyeball movement?

Greater inertia in stopping eye movement Signup and view all the answers

Which of the following is a role of the hypothalamus in stress regulation?

Regulate hormone production Signup and view all the answers

What happens to throw precision immediately after wearing glasses that shift the visual field laterally?

Throws become unprecise and lateral Signup and view all the answers

What type of damage to the cerebellum is typically non-reversible?

Stroke in brain Signup and view all the answers

Which condition indicates an inability to maintain equilibrium when the eyes are closed?

Dysequilibria Signup and view all the answers

How does damage to the cerebellum affect finger-nose coordination?

Finger does not reach the nose Signup and view all the answers

What describes the characteristic of intention tremor as it approaches its target?

Low frequency and high amplitude Signup and view all the answers

What does dysdiadochokinesia involve?

Rapid alternate movements Signup and view all the answers

What is a consequence of cerebellar damage when a person wears glasses that distort their visual field?

No corrective movements are made Signup and view all the answers

What condition is described by the inability to predict the distance to an object?

Dysmetria Signup and view all the answers

What common symptom is associated with cerebellar damage impacting coordination?

Loss of limb coordination Signup and view all the answers

What is typically observed in the motor responses of a person with cerebellar damage?

Frequent understating of targets Signup and view all the answers

What key role does the cerebellum play in speech?

Coordinates timing of muscle contractions Signup and view all the answers

What type of corrective action occurs immediately after wearing glasses that wrongly shift the visual field?

An instinctive overcompensation occurs Signup and view all the answers

In which scenario might you see symptoms of cerebellar damage if a person is stationary?

Eyes being closed Signup and view all the answers

What leads to the observation of nystagmus?

Oscillation of the eyeball Signup and view all the answers

What is the result of damage to the secondary hearing area?

Inability to recognize sounds or their sources Signup and view all the answers

Which area is responsible for coordinating both head and eye movements?

Secondary premotor area Signup and view all the answers

What is apraxia associated with?

Inability to perform complex movements Signup and view all the answers

Which mental functions are primarily associated with tertiary cortical areas?

Higher integrative functions such as memory and decision-making Signup and view all the answers

What characterizes the change in behavior observed in Phineas Gage after his accident?

Impulsivity and socially inappropriate behavior Signup and view all the answers

In functioning asymmetry, which type of dominance is related to the better analysis of visual signals?

Visual dominance Signup and view all the answers

Which area is primarily responsible for speech coordination?

Secondary premotor area Signup and view all the answers

What is the consequence of damage to the secondary visual area?

Visual agnosia where object recognition is impaired Signup and view all the answers

Which function is NOT associated with tertiary cortical areas?

Control of reflex actions Signup and view all the answers

What does sensory dominance refer to?

Greater proficiency in processing sensory information in one hemisphere Signup and view all the answers

What type of movements does the secondary supplementary area coordinate?

Complex voluntary movements of the body Signup and view all the answers

What is indicated by the term 'functional asymmetry' in the brain?

Certain functions are more dominant in one hemisphere than the other Signup and view all the answers

What does auditory dominance in the brain imply?

Greater efficiency in processing auditory information in one hemisphere Signup and view all the answers

Study Notes

Central Nervous System

Motor hierarchy arranges centers into three levels based on their input in movement regulation
Highest level (secondary and tertiary cortical areas) generates the general plan of movement, analyzing sensory information, and remembering
Middle level (primary cortical areas and subcortical centers) splits the general plan into programs, regulating movement
Lowest level (lower motor neurons in the spinal cord) activates skeletal muscles, enabling movement
There is a constant interaction between levels, with feedback from lower levels informing higher centers and modifying movement plans.

Functional Anatomy of the Spinal Cord

Spinal cord consists of white matter surrounding grey matter
White matter is made of nerve fibers for conductive pathways
Grey matter consists of nerve cell bodies and synapses
Afferent fibers (bringing information into the spinal cord) are in the dorsal root
Efferent fibers (taking information out of the spinal cord) are in the anterior root
Conductive function is related to the conductive pathways in the white matter
Reflex function is related to the reflexes organized through the spinal cord
Ascending pathways carry sensory information to the brain
Descending pathways carry motor signals from the brain to the spinal cord
Reflexes (like stretch reflexes) are organized through the spinal cord.

Early and Late Consequences of Spinal Shock

Spinal shock is a result of high spinal cord transection
Consequences depend on the level of the transection
Above C5 typically leads to death
Below C5, potentially results in spinal shock, which impacts respiratory function
Respiratory muscles (diaphragm and external intercostals) depend on impulses from the CNS
Muscles below the injury do not receive impulses from respiratory center so can't function
Damage above C5 means respiratory center cannot send impulses to muscles
If not treated quickly, irreversible brain injury can result.

Functions of the Medullary Region and Pons

Medullary region and pons are areas of the brainstem, immediately above the spinal cord
Conductive pathways through them join the spinal cord and the brain
Reflex functions (such as breathing, heart rate control, and defense reflexes)
Vital reflexes are important for survival

Functions of Midbrain

Located above the pons
Two functions: conductive and reflex
Conductive pathways connect the spinal cord and the brain
Reflex actions (visual orientation)

Functions of Cerebellum

Control motor activity (predicts the direction and intensity of muscle contractions)
Afferent information from everywhere informs the cerebellum about current movements
Plays important role in tasks like equilibrium control, coordinating and controlling muscle contractions, adjustments of ongoing movements.
Contains four key groups of nuclei (for a few different functional areas)
Different functional zones within the cerebellum (Vermis, hemispheres, flocculonodular lobe)

Functional Parts of Cerebellum & Damage Consequences

Cerebellum is divided into three lobes (posterior, anterior, and flocculonodular) for different functional zones.
Damage to the cerebellum leads to problems executing movements, balance issues, or emotional disturbances.

Functions of Hypothalamus

Regulates behavioral reactions and emotions, in concert with the autonomic, endocrine, and somatic nervous systems.
Controls thirst, satiety, sleep, body temperature, sexual function, stress reaction, and biological rhythms

Functions of Thalamus

Relay information going to the cerebral cortex
Connects various centers in the brain for common functions (like visual and auditory to sensory areas of the brain)
Plays a role in regulating emotions, sleep-wake cycles, alertness, and attention.

Functions of Basal Ganglia

Encode decisions to move
Regulate movements
Regulate expressions of emotions

Functions of Hippocampus and Amygdaloidal Nuclei

Located in the temporal lobe
Learning, spatial orientation, and memory
Damage leads to amnesia, trouble with spatial tasks and learning new information.
May play a role in social and emotional processes.

Circadian Rhythms & Sleep

Circadian rhythms are daily cycles (like sleep-wake)
The suprachiasmatic nucleus (SCN) of the hypothalamus controls circadian rhythms.
Affected by light (zeitgebers)
Regulates hormones, body temperature, mood, and alertness in a daily pattern.

Speech Mechanism

Three processes: phonation (sound production), resonance (modification of sound by the vocal tract), and articulation (shaping sounds into words)
Vocal cords vibrate to produce sounds.
Larynx, pharynx, mouth, nose modify sound.
Broca's area (generating speech) and Wernicke's area (comprehension).

Language Areas (Cerebral Cortex) and Consequences of Damage

Broca's area: responsible for language production.
Wernicke's area: involved in language comprehension.
Damage to either one leads to aphasia (language disorder)

Functional Asymmetry

The dominance of a particular cortical area on one side of the brain → usually corresponds to handedness
For example, most right-handed people have language dominance in the left hemisphere.

Calcium Metabolism and Hormone Control

Calcium is needed for numerous processes in the body
Parathyroid hormone (PTH) → increases calcium blood levels
Vitamin D (calcitriol) → regulates calcium absorption and regulation
Calcitonin → reduces calcium blood levels, decreasing osteoclast activity.

Endocrine Functions of the Pancreas (Somatostatin & Glucagon)

Secretions are controlled by various factors
Somatostatin inhibits other pancreatic hormones
Glucagon raises blood sugar

Insulin Synthesis and Regulation of Secretion

Insulin regulates blood glucose levels.
Produced by pancreatic islet cells (the β cells).
Regulated by blood glucose levels
Affects different body tissues for its action.

Effects of Insulin

Increases glucose uptake by cells to use for energy.
Reduces breakdown of glycogen, fat, and protein.
Promotes growth and repair of tissues.

Glucose Tolerance Test

Measures how well the body regulates blood sugar after consuming sugar.
Diabetes is often detected with a glucose tolerance test.

Effects of Insulin Deficiency (Diabetes Mellitus)

Diabetes is a group of diseases characterized by elevated blood glucose.
Results from problems with insulin secretion, insulin action, or both.
Effects include increased glucose in the blood (hyperglycemia), which can cause damage to tissues (especially blood vessels).
Glucose loss increase (through kidneys)

Sex Hormones and Regulation of Sexual Function

Male: Testosterone (regulated by LH and GnRH)
Female: Estrogen and Progesterone (regulated by FSH and LH and GnRH)
Important for sexual development of both sexes, reproduction, and associated physical characteristics

Regulation of Male Sexual Function

Regulation of spermatogenesis and sperm maturation in the testes.
Regulation of sexual function during intercourse (erection, emission, and ejaculation).

Regulation of Female Sexual Function

Regulation of menstrual cycle (FSH, LH, estrogen, progesterone).
Regulation of sexual arousal and orgasm.

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