MBB EXAM 2

neuromuscular, motor, parkinsons, alzheimers, stroke, ALS

Polyneuropathy

Damage to terminal branches on multiple nerves 

parkinsons 

decreased dopamine signaling in basal ganglia due to DEGENERATION of DOPAMINE producing cells 

diabetes, vitamin B 12 deficiency, GBS

conditions associated with POLYNEUROPATHY

Mononeuropathy

Damage to single peripheral nerve

Mononeuropathy multiplex

Damage to ≥ 2 peripheral nerves

Radiculopathy

Damage to nerve root

lumbar disc and GBS

conditions associated with RADICULOPATHY

Plexopathy

Damage to a nerve plexus 

Axonal neuropathy

a disorder affecting AXONS leading to muscle weakness and sensory loss

Demyelinating neuropathy

disorder that damages MYELIN sheath, causing weakness, numbness, and impaired coordination

Guillain-Barré syndrome (GBS)/ AIDP

Immune-mediated inflammation leads to damage of nerve myelin or axons

Areflexia

absence of reflexes, often associated with GUILIAN BARRE SYNDROME (GBS)

radiculopathy and polyneuropathy

neuropathies associated with GBS

pharyngeal-cervical-brachial variant

severe form of Guillain-Barré syndrome (GBS) that affects BULBAR FUNCTION

bulbar

functions related to the cranial nerves that control chewing, swallowing, and speech

Guilain-Barré syndrome (GBS)

Antibodies against GANGLIOSIDES

Guilain-Barré syndrome (GBS)

Molecular mimicry by campylobacter jejuni

Myasthenia gravis

Antibodies against ACETYLCHOLINE RECEPTORS

Lambert-Eaton myasthenic syndrome

Antibodies against voltage-gated CALCIUM channels

botox

Toxin inhibiting ACETYLCHOLINE RELEASE into synapse

amyotrophic lateral sclerosis (ALS)

A patient presents with arm weakness. He is hyperreflexic in his right arm, but also has atrophy and fasciculations in the muscles of his right hand. You are concerned about what motor neuron disease?

motor neuron involvement/damage

what does arm weakness indicate?

Hyperreflexia

an exaggerated reflex response

hyperreflexia, spasticity, and stiffness

sign of UPPER MOTOR NEURON (UMN) lesions

Atrophy and fasciculations

signs of LOWER MOTOR NEURON (LMN) damage

Hereditary myopathies

MYOPATHIES that are chronic, SLOWLY progressive, family history, no inflammation, often structural changes in muscle

Acquired myopathies

MYOPATHIES that are more RAPID onset, systemic associations, may respond to treatment, often inflammatory or toxic

ALS

Progressive weakness which can involve bulbar,extremity, respiratory muscles

frontotemporal dementia

what disease is ALS sometimes associated with? 

ALS

progressive degeneration of both UPPER and LOWER motor neurons

neuropathy

a disorder affecting the peripheral nerves, causing weakness, numbness, and pain

mononeuritis multiplex

what type of neuropathy would have the following distribution? 

mononeuropathy

what type of neuropathy would have the following distribution? $

polyneuropathy

what type of neuropathy would have the following distribution? 

plexopathy

what type of neuropathy would have the following distribution? 

radiculopathy

what type of neuropathy would have the following distribution? 

Frontal lobe

Controls executive functions (planning, judgment, decision-making), voluntary movement (primary motor cortex), speech production (Broca's area, left hemisphere), working memory, and aspects of personality

dominant (left) hemisphere

controls language, logical reasoning, math, praxis, and verbal memory

non-dominant (right) hemisphere

controls visuospatial, emotional processing, emotional language, auditory and visuospatial memory, and muscle perception

Temporal lobe

involved in processing auditory information, language comprehension (Wernicke's area), memory, and emotional responses

Parietal lobe

involved in processing sensory information, spatial awareness, attention, and integrating sensory input.

hemispatial neglect

a condition where an individual fails to attend to stimuli on one side of space, typically due to damage to the RIGHT PARIETAL lobe.

left hemispatial neglect 

what can damage to RIGHT PARIETAL (nondominant) lobe cause

Occipital lobe

Interprets visual information from both eyes; each lobe processes vision from the opposite field

Cerebellum

Coordinates fine motor movement and balance, posture, and motor learning

ipsilateral

what is the coordination of the cerebellum (ipsilateral or contralateral) 

brainstem

Vital for basic life functions (breathing, heart rate, arousal), transfers information between brain and body, and houses nuclei for most cranial nerve

 corpus callosum

A thick band of nerve fibers that connects the left and right cerebral hemispheres, facilitating INTERHEMISPHERIC communication

association cortex

integrates signals from widspread connection across brain to allow for higher cognitive functions such as perception, language, and decision making

gerstmann syndrome

damage to LEFT sensory association cortex (parietal) resulting in agraphia, acalculia, finger agnosia, and left-right disorientation

Aphasia

disorder of LANGUAGE, due to damage to language-related cortex (usually left hemisphere)

Dysarthria

speech ARTICULATION dysfunction

Broca's aphasia

can't produce fluent speech, but comprehension mostly spared

Wernicke's aphasia

speech fluent but nonsensical; poor comprehension

Conduction aphasia

difficulty in repeating phrases; fluent speech

Global aphasia

severe impairment of BOTH comprehension and production

impaired speech (brocas aphasia)

damage to this area would cause?

impaired repetition (conduction apahsia)

damage to this area would cause? (arcuate fasciculus)

impaired comprehension (wernickes aphasia) 

damage to this area would cause?

prefrontal cortex

controls executive planning such as: concentration, judgment, reasoning, PLANNING

limbic

What system in the brain is responsible for EMOTION and MEMORY PROCESSING?

hippocampus 

region of LIMBIC system responsible for MEMORY 

amygdala

region of LIMBIC system responsible for EMOTIONS

agnosia

inability to recognize or interpret sensory information despite intact primary sensory modalities (ex: recognition of objects, faces, or sounds)

astereognosis

form of agnosia where a person cannot identify objects by touch, despite having intact tactile sensation

Hypokinetic

Too little movement (bradykinesia, rigidity, akinesia)

parkinsons disease, drug-induced parkisonism

examples of HYPOkinetic movement disorders

bradykinesia (slowness of movement) 

Defining feature of Parkinson's

Drug-induced Parkinsonism

decreased dopamine due to blocking of dopamine receptors by antipsychotic drugs (1st gen)

Hyperkinetic

too much involuntary movement

essential tremor, Huntington's disease, dystonia, tourettes syndrome

examples of HYPERkinetic movement disorders 

Rest tumor/Pill rolling tremor

tremor occurs when muscles are not voluntarily activated (classic for Parkinson's)

Action tremor

What type of tremor is characteristic of essential tremor?

Rest tremor 

What type of tremor is characteristic of Parkinson's?

Action tremor

tremor occurs during voluntary muscle contraction

Essential tremor

neurological disorder characterized by rhythmic tremors during voluntary movements (ACTION TREMORS), often affecting the hands

Propranolol (beta-blocker), primidone (barbiturate anticonvulsant

First-line pharmacological treatment options for essential tremor

Blocks beta-adrenergic receptors (reduces activity in muscle and possibly GABA modulation)

Propranolol MOA

Blocks voltage-gated Na channels (enhances GABAergic inhibition)

Primidone MOA

Fatigue, bradycardia, low blood pressure

Propranolol side effects 

Sedation, dizziness, nausea

Primidone side effects

Motor (chorea), cognitive (decline), behavioral (mood changes)

clinical triad of Huntington's Disease

30–50 years

Usual age of onset of huntingtons disease

Chorea

involuntary, irregular, dance-like movements, often seen in HUNTINGTONS disease

antipsychotics (block dop receptors) and VMAT2 inhibitors (reduce dop release)

Treatments for chorea

Huntington gene on short arm of chromosome 4

What genetic mutation is related to Huntington's disease

autosomal dominant

inheritance pattern of huntingtons disease

Dystonia

SUSTAINED muscle contractions, abnormal postures, or twisting movements

Writer's dystonia

task-specific focal dystonia that causes involuntary muscle contractions in the hand and forearm, primarily during writing

Tics

Sudden, brief, repetitive movements or vocalizations

Tourette's syndrome

BOTH multiple motor and at least one vocal tic for >1 year, onset before age 18

tics bother patient

When should toureettes be treated?

benzodiazepines, alpha-adrenergic receptor agonist, VMAT2 inhibitors, dopamine blockers

Drugs used to treat tourettes

botox

cleaves SNARE proteins, preventing release of acetylcholine 

focal dystonia

When might botox be used as a medical treatment?

Dyskinesia

variety of involuntary motor movements (ex: chorea, dystonia, tic tremor ext) 

Tardive dyskinesia

HYPERkinetic movement disorder caused by exposure to dopamine-BLOCKING agents 

 discontinue offending drug (if possible), avoid 1st gen antipsychotics, VMAT2 inhibitors

Treatment for tardive dyskinenia

lesodopa -induce dyskinesia

side effect of drug used to treat PARKINSONS

Hypokinetic movement disorders

decreased dopamine signaling the basal ganglia