Neuropsychology Lecture Notes PDF

**Neuropsychology** **Lecture 1** Gray matter mostly made of cell bodies White matter mostly made of myilated bodies, can grow back😊 Brain lesion: - Area of brain damage - Can result from stroke, loss of blood Principles of organization - Localization: injury in an anatomical location...

**Neuropsychology** **Lecture 1** Gray matter mostly made of cell bodies White matter mostly made of myilated bodies, can grow back😊 Brain lesion: - Area of brain damage - Can result from stroke, loss of blood Principles of organization - Localization: injury in an anatomical location that leads to the same symptoms - Lateralization: injury on this side of the brain usually lead to damage in language function - Distribution of functions: sometimes other brain areas start to compensate for the damage - Hierarchical organization: sophistication of functions varies depending on whether a higher or lower brain area is damaged - Hindbrain - Midbrain - forebrain History of neuropsychology - Donald Hebb: father of neuropsychology - Hebbian theory; neural pathways develop based on experiences: as pathways are used more, they become stronger and faster - Early neuropsychology was closely linked to brain injury and dementia research and diagnosis - Relationship between loss of brain function and change in thoughts easier to observe The Hebbian assumption of change Bio -- psycho -- social model: a person is not made of isolated organs Dementia: umbrella term for impaired memory, cognition, and decision-making - Common causes: Alzheimer's, Huntington's, multiple sclerosis - Symptoms include poor mood and perception Biopsychosocial perspective in dementia - Usually applied as part of treatment plan - External triggers are assessed through history interview - Social support and environmental well-being considered in treatment plan - Part of our social well-being is our cultural fit - Beliefs from our community shape our experience of medicine - Not all symptoms are symptoms - Certain beliefs are cultural - Sometimes hallucinations are even considered culturally appropriate - Cultural formulation interview - Used to determine whether something is pathological Genetic theories - Mendel -- Classic genetics - Lamarck -- Epigenetic code and phenotypic plasticity **Lecture 2** Neuropsychologists rely on primarily information about larger brain structures and functions - Global functions appear state-based (fixed) Understanding nerve cells is crucial Types of MS (multiple sclerosis) - Primary progressive - Symptoms set and progressively get worse - No history of remission - Relapsing remitting - Relapse = active symptoms / myelin damage - Symptoms disappear and reappear across time - Progressive relapsing - Like RRMS but symptoms become increasingly disabling - Very rare - Secondary progressive - Occurs after patient previously had RRMS - Remissions stop, symptoms get worse Sclerosis = scars (on axons) Types of neurons: - Bipolar: rare, mostly in ear, nose, eyes - Two extensions from the cell body including one axon and one dendrite - Multipolar: common, throughout the CNS - Multiple extensions from the cell body, including one axon and many dendrites Pyramidal cells: a type of multipolar neuron found in areas of the brain including the cerebral cortex, the hippocampus, and the amygdala Epigenetic changes - The epigenome mains, modifies, and regulates genes - Determine which genes are expressed DNA methylation - Methyl groups are added to the DNA molecule - Methyl group = 1 carbon and 3 hydrogen atoms - Adding methyl group blocks promoters from expressing the gene Histone methylation - Changes in histone methyl groups can induce or repress gene expression Neural communication - Cortical neuron: located in the cerebral cortex, involved in higher cognitive functions such as perception, reasoning, and motor control - Thalamic neuron: located in the thalamus, which acts as a relay station for sensory and motor signals to and from the cortex, these neurons help transmit and process sensory information and coordinate motor activity Summation - Process in multiple signals combine to affect a neurons overall activity - Temporal summation: a rapid series of weak pulses from a single source convert into one large signal - Spatial summation: several weak signals from different locations are converted into one large signal Backpropagation - Hebbian plasticity = brains learn from life experiences - Neurons back propagate - In artificial neuron networks, it results in adaptive changes Neuroplasticity - Plasticity: structural reorganization after learning or injury - Homologous are adaptation = opposite hemisphere takes over a sensory/cognitive process - Cross-modal reassignment = loss of one sensory/cognitive process heightens the remaining senses - Map expansion: some areas take on new functions to compensate for loss - Compensatory masquerade = brain uses alternative pathways for processing in place of a lost ability - Flexibility: adaptive functional changes How neural communications affect systems and behaviours - Cholinergic system - Sends messages in the brain and body - Muscle movement - Thinking and memory - Body functions - Dopaminergic system - Active in maintaining normal motor behaviour - Noradrenergic system (Norepinephrine) - Active in maintaining emotional tone - Decreased leads to depression - Increased leads to mania - Serotonergic system - Active in maintaining waking electroencephalographic (EEG) pattern Cellular recordings Single cell recording: **Lecture 3** Cerebellum holds more than half of the neurons in your whole body - 90% of motor and somatosensory fibres cross over The brains blood flow - Anterior cerebral circulation - Anterior cerebral artery - Middle cerebral artery - Posterior cerebral circulation -- provides blood to the occipital lobes, cerebellum, brainstem and posterior brain Strokes 1. Ischemic stroke (clots) - Embolic - Thrombotic 2. Haemorrhagic stroke (bleeds) - Subarachnoid - Intracerebral Apraxia = left-hemisphere lesions make it difficult to make or copy voluntary movement sequences **Lecture 4** The neural tube - Formed in the fetus, three main parts - Forebrain - Midbrain - Hindbrain Early brain development - Cell migration and differentiation - Occurs 4-5 months before birth to 8 months after - Similar types of cells aggregate in distinct regions Piaget theory, stages of infantry 1. Sensory motor development, age 0-2 2. Pre-operational stage, age 2-4, 4-7 years of age 3. Concrete observational stage, 7-9, 9-11 4. Formal operational stage, 11-14, 15-17 Plasticity - Experience-expectant plasticity = high overlap across individuals - Experience-dependent plasticity = experiences are relatively unique **Lecture 4** 10 levels of cognitive functioning 1. No response: total assistance 2. Generalized response: total assistance 3. Localized response: total assistance 4. Confused/agitated: maximal assistance 5. Confused, inappropriate non-agitated: maximal assistance 6. Confused, appropriate: moderate assistance 7. Automatic, appropriate: minimal assistance for daily living skills 8. Purposeful, appropriate: stand-by-assistance 9. Purposeful, appropriate: stand-by-assistance on request 10. Purposeful, appropriate: modified independence **Lecture 5** Why is human variation important for neuropsychologists to understand? Handedness: - One theory attributes right-handedness to grater development of the left hemisphere - Another theory says that animals have left-sided developmental advantage Sex differences in brain structure and function - Some sex related differences in brain asymmetries - Women have more interhemispheric connections, in both the corpus callosum and the anterior commissure - The posterior part of the callosum is larger in women - Left wernickess\`s is larger in men sometimes - Men have larger sylvian fissure - The right planum parietale (spatial awareness) is about twice as large in men Congenital disorders - Hydrocephalus - Detected through a prenatal ultrasound between 15 and 35 weeks gestation - An imbalance between how much csf fkuid is produced and how much is absorbed - Can be treated through surgery - Obstruction of csf - Build up of pressure - Usually develops in infancy - Enlarged ventricles, brain shrinkage - Cerebral palsy - A group of disorders that affect a persons ability to move and maintain balance and posture - Emerges prenatally due to damage to white matter, possibly as a result of reduced blood or oxygen supply - More common among boys Partial fatal alcohol syndrome Alcohol-related neurodevelopmental disorder Alcohol related birth defects Neurobehavioral disorders associated with prenatal alcohol exposure Down syndrome - Congenital condition caused by the presence of an additional copy of chromosome 21 - Down syndrome also called trisomy 21 - Congenital condition = present at birth - Physical traits - Lower IQ - Sometimes high social intelligence Fragile X syndrome - Usually diagnosed at 20 months (boys) and 26 months (girls) - Males are usually more severely affected - Leading genetic cause of autism only single- gene cause of autistic symptoms - A gene called FMR1 usually makes a protein called FMRP; this process is absent in FX patients **Lecture 6** Exteroceptive -- respond to external stimuli Interoceptive -- respond to internal stimuli Perception: - Embodied: influenced by other bodily states (hormones, physiology) - Embedded: influenced by the environment and past experiences - Our sensory impressions are affected by the contexts in which they take place The human eye - Cornea: the clear membrane covering the visible part of the eye helps gather and direct incoming light - Iris: coloured part of the eye the muscle that controls the size of the pupil - Pupil: opening in the middle of the iris changes size to allow different amounts of light to enter the eye - Lens: transparent structure located behind the pupil actively focuses, or bends, light as it enters the eye - Retina: thin, light-sensitive membrane located at the back of the eye contains sensory receptors Depth cues - Texture gradient: elements tend to appear more closely packed together as the distance from the view increases - Stereopsis: the ability to perceive 3D because two eyes receive slightly different view of the world - Motion parallax: provides 3D information when an object is in motion a - As more distant points move, they will move more slowly across the retina than closer points Astigmatism: when your cornea or lens has a different shape than normal, creating two or more image points on the back of the eye Functions of the visual cortex: - V1: segregates pattern vision from motion signals - V2: 3D vision, seeing more complex patterns - V3: shape perception - V4: colour area and shape perception what pathway, ventral - V5: motion area where pathway, dorsal Fusiform gyrus: the region of the temporal love that responds when face are present in the visual field Semantic regularities: functions common to a scene Scene schema: knowledge of what a scene typically contains Bayesian inference: - Prior probability: our beliefs about the probability of an outcome Disorders: - Blindsight: lacking conscious awareness of visual experience, but being able to respond to those experiences anyway, damage to V1 - Visual agnosia: the inability to recognize visual objects, which is neither a function of general intellectual loss nor a loss of basic sensory abilities - Apperceptive agnosia: unable to recognize objects, draw, or copy figures - Associative agnosia: difficulty understanding the meaning of what they are seeing, can draw or copy but do not know what they have drawn - Prosopagnosia: face blindness - Visuospatial agnosia: difficulty with the spatial relationship between objects used **Lecture 7 the temporal lobe** Temporal lobe epilepsy (TLE) - Epilepsy: a condition that causes frequent seizures Types of seizures - Focal onset: most common, person is unaware - Generalized onset: person loses awareness - Unknown onset: happens when the seizure isn't witnessed by anyone and the patient doesn't remember whether or not they were aware during Tonic-clonic seizures - Sings of onset - Tonic phase: sudden stiffness - Clonic phase: repeated jerking movement - Postitical period: after a seizure when the brain is recovering Anatomy: - Superior temporal gyrus: auditory processing - Inferotemporal cortex: visual processing - Pyriform cortex: olfactory processing and memory - Corpus callosum: bilateral communication Dichotic listening and the visual object and space perception battery assess auditory and visual processing capacity Wechsler memory scale assesses verbal memory ability Rey complex figure test assesses nonverbal memory ability Token test assesses comprehension **Lecture 8: parietal lobe** Association Areas Limbic association area: anterior-ventral temporal lobe: - links emotion with many sensory inputs. Important for learning and memory Posterior association area: junction of occipital, temporal and parietal lobes: - Links information from primary and unimodal sensory areas; important in perception and language Anterior association area: prefrontal cortex - Links information from other association areas, important in memory, planning, and high-order concept formation Extrastriate body area (EBA) - Located in the lateral occipito-temporal cortex - A body selective focal region - Responds strongly to images of human bodies and body parts in comparison with other classes of stimuli Parietal functions by zones - Anterior zone = somatic sensations and perceptions - Posterior zone = sensory integration and whole-body movement - Network connects to all other lobes Superior parietal lobe: visuomotor, cognitive, sensory, higher order, working memory and attentional - Spatial orientation - Needs for visual perception - Where something is - Includes object manipulation Inferior parietal lobe: spatial attention, multimodal sensory integration, and oculomotor control - Spatial attention and multimodal sensory integration - Needed for visual perception - Paying attention to movement - Produces complex sensory experiences Somatosensory cortex - Detects sensory information from the body regarding temperature, 1. Dorsal column-medial lemniscus pathway: transmits pressure 2. Spinothalamic pathway: pain, temperature, and crude touch The precuneus - Recollection and memory - Default mode network = brain processes when brain is at a rest Posterior cingulate cortex - Controlling state of arousal, the breadth of focus and the internal or external focus of attention - Self-referential processing, episodic or autobiographical memory, future thinking, mentalizing, spatial navigation, and conceptual processing Temporal-parietal junction - Facilitates social cognition, attention, and language processing Asomatognosis - A loss of knowledge of ones body usually considered a type of agnosia caused by parietal lesion - Anosognosia = unawareness/denial of illness - Anosodiaphoria = indifference to illness - Autopagnosia = inability to localize / name body parts - Asymbolia for pain = absence of typical pain response Gerstmann\`s syndrome - Left parietal stroke - Finger agnosia - Left-right confusion - Agraphia = inability to write - Acalculia = inability to perform arthimatic Balint syndrome **Lecture 9 the frontal lobe** Three primary types of cultural transmission - Vertical = from parent to child - Oblique = from older generation to younger gen - Horizontal = between peers Subdivisions: - Dorsolateral prefrontal cortex -- executive functions, like problem solving - Ventrolateral prefrontal cortex -- response inhibition, stopping yourself from saying something - Premotor cortex -- plans voluntary movement - Primary motor cortex -- controls voluntary movement - Orbitofrontal cortex -- decision making - Dorsomedial prefrontal cortex -- self-reflection, social cognition - Ventromedial prefrontal cortex -- emotion regulation - Anterior cingulate cortex -- error detection, conflict monitoring Functional systems - Limbic system - Emotion regulation - Memory and motivation - Social brain networks Paul Eckman -- basic emotions were recognizable cross-culturally Emotion and the social brain - Helmholtz\`s unconscious inference we use intuition instead of metacognition **Lecture 10** Cognitive disorders: systematic difficulties with processes related to knowing Psychiatric disorders: systematic difficulties with thoughts, behaviours, and emotions Neurological disorders: structural, biochemical or electrical abnormalities Language disorders - Paraphasia = adding syllables Dyslexia - Attentional dyslexia: multiple letters or words cause difficulty - Neglect dyslexia: may misread the first or last part of the world - Letter-by-letter reading: affected persons read words only by spelling them out - Phonological dyslexia: inability to read nonwords aloud - Surface dyslexia: cannot recognize words directly Attention - Selective attention: paying attention to one thing while ignoring others - Divided attention: paying attention to more than one thing at a time - Attentional capture: shift of attention to very salient stimuli The study of attention and Serial Bottlenecks - Early selection theories: - Filter occurs before we perceive the stimulus - Late selection theories - Filter occurs after we perceive the stimulus Broadbent\`s filter theory Spatial navigation **Lecture 11** Migraines = a neurological disorder Secondary headaches - When the headache is a symptom - 150 different types with a different causes Tumours: - When glia or other support cells form a mass with no physiological functions - Can be malignant or benign - Can put pressure on the brain or not - Can be filled with fluid - Can cause seizure or epilepsy **Lecture 12: Psychiatric disorders** Roy Grinker: applied bio George Engel: applied socio Cholinergic system: plays a role in memory, being awake Dopamenergic system: might be related to adhd, is connected to addiction Noradrenergic system: active in maintaining emotional tone Cingulotomies: biliteral cingulotomy Schizophrenia: - Fewer synapse in dorsolateral prefrontal cortex - Pyramidial neurons in the hippocampus have haphazard orientations - Biochemical differences in the dopaminergic system more dopamine than usual 1. Must be born with certain genes 2. Stressful life events trigger epigenetic changes 3. Schizophrenia emerges Mood disorders 1. Major depression 2. Bipolar disorders Bipolar disorder  - Euthymia: base mood - Subsyndromal depression - What causes the autonomous recurrence of episodes? One possibility is that the bipolar patients brain is especially sensitive to the effects of stressors or drugs and that episodes of mood disorder actually change the brain - Grey matter atrophy: - Temporal lobe (fusiform gyrus and hippocampus) - Cerebellum Anxiety disorders 1. Panic disorder -- can have specific trigger, or more general 2. Posttraumatic stress disorder - 3. General anxiety disorder 4. Obsessive-compulsive disorder 5. Specific phobias Types of dementias: 1. Tauopathies: tau is a protein inside neurons - Alzheimers - Corticobasal degeneration - Fronttemporal 2. Synucleinopathies 3. Vascular dementias and vascular cognition impairment 4. Mixed demetias Alzheimers - Cell changes in the cortex and hippocampus Review of assumptions of change and its mechanisms Homologous area adaptation = opposite hemisphere takes over a sensory/cognitive process Cross-modal reassignment = loss of one sensory / cognitive process heightens the ramining senses Map expension = some areas take on new functions to compensate for loss Genetic theories - Mendel -- classic genetics - Lamarck -- epigenetic code and phenotypic plasiticity **Lecture 13 in the clinic** Prolonged stress seems to influence the hippocampal neurons harder time to remember stuff Clinical neuropsychology: 1. Assessment 2. Treatment and interventions 3. Consultation 4. Research 5. Teaching and supervision Metabolic tolerance: you need more enzymes to break down the same amount of drugs Cellular tolerance: getting used to the drug Learned tolerance: individuals adapt to the effects of the drug through experience, leading to a decreased response to the drug over time Sensitization: occurs with drugs and also with stress Hedonic theory of addiction: suggests that the user takes a drug because they liked it Epigenetic factors are related to these three influences - Depend on epigenetic changes Group 1. Antianxiety agents and sedative hypnotics Group 2. Antipsychotic agents Group 3. Antidepressants and mood stabilizers Group 4. Opioid analgesics Group 5. Psychotropic drugs **Lecture 14; review**