Neuropsych MCQ Test

Cognition

Mental process (or thought processes)

Neuropsychology

Concerned with the integration of neurological observation of brain damage and psychological observations of behavior and cognition

Spinal cord

Where sensory information enters the CNS (dorsal portion) and motor commands exit CNS (ventral portion)

Skull

Provides protect for brain, most important

Dura mater

Hard meninges

Arachnoid membrane

More playable, contains cerebrospinal fluid

Pia Mater

Close to brain surface - Soft

Neurons

Signaling units (main)

Glial cells

Supportive cells, really important functions

Nerve cells function

Communication via electrician and chemical signal

Structure of nerve cells

Cell Body, dendrites, axons, presynaptic terminal

Cell body of nerve cell

Stoma, metabolic center of neuron

Dendrites

Treelike processes that receive input (post synaptic)

Axons

Tubular process extending to 1 meter, the main conducting unit of the neuron

Presynaptic terminals

Fine branches at the end of the axon, transmit info to other neurons; where this neuron can communicate with other neurons

Neuron communication

Axon of presynaptic cell transmits info to dendrites of the post synaptic cell (flows across synaptic cleft)

Synapse contents

Presynaptic ending with neurotransmitters, postsynaptic ending that contains receptor sixties for neurotransmitters, synaptic cleft (space between pre and postsynaptic)

White matter

Axons myelinated

Grey matter

Cell bodies

Blood supply to brain

Brain cells depend on an adequate supply of oxygen and nutrients through a dense network of blood vessels

Carotid arteries

Anterior part of brain - in front of vertebral arteries

Vertebral arteries

Irrigates posterior, basilar arteries supply the posterior cerebrum, cerebellum, and brain stem

Anterior cerebral artery

Medial sections

Middle cerebral artery

Lateral sections

Posterior cerebral artery

Inferior part of temporal lobe and occipital lobe

Frontal lobe

Contains primary motor cortex (in the pre central gyrus)

Parietal lobe

Contains primary somatosensory cortex which is in the post central gyrus

occipital lobe

Contains primary visual cortex

Temporal lobe

Contains primary auditory cortex

Corpus callosum

Main fibre tract connecting the 2 cerebral hemispheres

Insular cortex

Inside the lateral sulcus

Cerebellum

Large structure attached to the dorsal aspect of the brain stem

Cerebrospinal Fluid (CSF)

Liquid surrounding brain; provides both protection and metabolic needs

Lateral sulcus

Separates the temporal lobe from the frontal and parietal lobe

Central sulcus

Separates frontal and parietal lobes

Frontal lobe

3 gyri (superior, middle, inferior), runs anterior - posterior meeting the pre central gyrus at pre central sulcus

Temporal lobe

Superior, middle and inferior gyri

Parietal

Posterior gyrus (plus the superior and inferior parietal lobules separated by intraparietal sulcus)

Thalamus

Subcortical structure; 1 in each hemisphere

Ventricular system

Interconnected cavities with CSF, Lateral ventricles (2), IIIrd ventricle, cerebral aqueduct, IVth ventricle

Brain stem function

Life-sustaining function (heartbeat, breathing, arousal and alertness); inferior colliculi (audition) and superior colliculi (visuomotor functions)

Spinal cord

Primarily conducts the final motor signals to muscles and receives sensory information and relays it to the brain; contains reflex pathways

Primary motor cortex

Outputs motor commands, contains motor neurons whose axons extend down the spinal cord and synapse on neurons that innervante your muscles (anterior to central sulcus)

Primary somatosensory cortex

Parietal lobe (in post central gyrus); receives input about somatosensation (relayed through thalamus)

Primary Visual cortex

Receives visual inputs (through thalamus); located primarily on medial surface of occipital lobe and buried in calcarine fissure

Primary auditory cortex

Receives auditory inputs (through thalamus); located in superior part of the temporal lobe and buried in lateral sulcus

Association Cortex

Information from multiple modalities converges for processing

CT Scan (computed tomography)

Anatomical view of brain by X—ray beams through head, creates cross sectional 2D images that show STRUCTURE of brain not function

MRI (magnetic resonance imaging

More detailed anatomical view of brain; depends on magnetic properties of brain tissue (3D map in 2d form)

Diffusion Tensor Imaging (DTI)

Provides view of white matter tracts (axons) , can determine health of these

Angiography

Image of vasculature of brain; size and location of blockages to be evaluated and to detect problems with blood vessels

EEG (electroncephalography)

Provides recording of the brain’s electrical activity; used to pick up abnormal electrical (neuronal) activity

Transcranial magnetic stimulation

Used to test the integrity of motor pathways, are cells intact (?); measured by EMG

Position emission tomography (PET)

Detects radioactive material; measures regional cerebral blood flow

fMRI

Records changes related to metabolic activity, better spatial resolution than PET

Stroke

Part of the brain is deprived of blood, without blood cells die (carry oxygen and nutrients to brain and can become blocked or burst)

Ischemic strokes

Clogged blood vessel, motor dysfunction is common symptom; 80% of strokes, occur because inadequate blood supply to a region of brain for enough time to cause death of brain cells

Thrombotic ischemic stroke

A blood clots forms __locally__ usually at a site of arteriosclerosis

Embolie ischemic stroke

A blood clot forms at another part in the circulatory system and travels through the bloodstream until it reaches a part of a vessel in the brain that is too narrow to pass

Arteriosclerosis

Characterized by abnormal thickening and hardening of arterial walls due to deposits in inner lining of an artery; __narrowing of arteries due to build up__

Hemorrhagic strokes

Ruptured blood vessel (weakened one ruptures); less common (20%)

Aneurysm (hemorrhagic stroke)

An abnormal bulge in a blood vessel due to weakening of vessel walls

Arteriovenous malformation (AVM) Hemorrhagic stroke

A congenital disorder characterized by a clusters of abnormal connections between arteries and veins

Transient Ischemic Attacks (TIAs)

Mini strokes, obstruction (blood clot) occurs for a short time and tends to resolve itself through normal mechanisms; typically about 10 minutes

Microglia

Devour and remove debris left by dead or degenerating brain cells (takes a long time)

Brain tumors

Caused by uncontrolled growth of brain cells; gliomas; both malignant and benign are harmful because they increase pressure in skull

epilepsy

Neurological condition characterized by excessive and abnormally patterned activity in brain (Seizures)

Seizures

Vary from a momentary disruption of sense to short period of unconsciousness or staring spells to convulsion caused by a brief electrical disturbance in brain (EEG used)

Generalized seizures

Involve the whole brain

Partial seizures

Start in 1 part of the brain and may stay in that part or may spread

Motor control

Ranges from simple reflexes (automatic) to volitional movements (controlled)

Afferon neuron

Connected to muscle spindle, which detects stretch in the muscle

Efferent neuron

The motor neuron that causes the reflexive movement

Spinal Reflexes (3 neuron loop)

1. Person steps on a thumbtack
2. The impact on the cells that the tack contacts is translated into a signal that travels up sensory nerve fibers
3. In a spinal cord, the info is transmitted to interneurons some of which synapse on motor neurons that send descending signals to relevant muscles
4. Motor command causes contraction of the relevant muscles and rapid withdrawal of foot

Motor Control

Regulated by a distributed network of cortical and subcortical structures, cortical neurons modulate the activity of reflex circuits in order to orchestrate coherent goal-directed behavior

Cerebral control of motor behavior, motor tracts

Brain has multiple routes through which information is transmitted from the brain to the muscles (motor movements planned in the brain are sent to target muscles to be executed)

Corticospinal tract

From primary motor cortex to spinal cord; primary motor cortex to corona radiata to internal capsule to midbrain to pyramid (medulla) to decussation (midline cross) to spinal cord

Corona radiata

Axons leaving precentral gyrus - join large body of axons to form

Internal capsule

Axons travel deeper into the hemispheres, pass between caudate and putamen

Brain stem (Crus cerebri)

Axons exit cerebral hemisphere and enter upper part of brain at midbrain

Pyramids of medulla

Axons pass through the pons and form pyramids, axons cross the midline, thus motor cortex in each hemisphere controls the opposite side of body

Spinal cord

Corticospinal axons synapse on neurons in the ventral horn

Primary motor cortex and stroke

A stroke affecting neurons in precentral gyrus can cause contralesional weakness or paralysis so neurons can no longer innervate the muscles they indirectly project

Primary motor area

Gets the movement going

Supplementary motor area

More important for planning movement

Cortical control over reflexes

Cortical neurons modulate the activity of reflex circuits in order to orchestrate coherent goal-directed behavior

Visual grasp reflex

Reflexive eye movements, visual grasp reflex refers to a rapid eye movement triggered by the sudden appearance of a visual signal in periphery (superior colliculi system plays important role)

Frontal eye field

Important role in generating voluntary eye movement (choice); at the intersection of superior frontal sulcus and precentral sulcus

Oculomotor system

Behavior is determined by cells in a number of brain areas at subcortical and cortical levels; mediate ore primitive reflexive oculomotor responses

Top-down circuitry

Movements when you want to and control reflexive circuitry when you don’t

Alien Hand Syndrome

Causes them to unintentionally reach out and grasp objects with affected arm; __trouble with control not moving__

Atrophy

Decrease in size or wasting away of a body part or tissue (brain)

Neurodegeneration

A decline in the structure and function brain cells

neurodegenerative diseases

Characterized by gradual and progressive loss of neural tissue (symptoms get worse over time)

Dementia

Characterized by a loss of cognitive functions that interferes significantly with work or social activities

Alzheimer’s Disease

95% sporadic/not hereditary; diffuse damage especially to cortical cells (including hippocampa); __decline in memory and other aspects of cognitive function__

Pick’s Disease

More rare, presents similar to Alzheimer’s, 90% sporadic, causes cerebral atrophy that mainly involves Frontal and Temporal Lobe

Huntington’s Diseases

**Hereditary;** Destroys neurons in caudate and putamen (striatum), causes the head of caudate to shrink and the anterior horns of lateral ventricles to dilate; symptoms include chorea (decreased motor function) and decline in cognitive functioning

Parkinson’s Disease

Unknown cause; dopaminergic cells in the substantial nigra; symptoms - tremors, rigidity, akinesia, bradykinesia, posture/gait/balance problems

Substantia nigra and PD

Rich in black pigment and dopaminergic neurons, PD kills dopaminergic neurons in substantia nigra