EPPP — Biological Bases: Core Systems & High-Yield Distinctions

Open-response recall cards built from Biological Bases practice rounds. Emphasizes localization, extrapyramidal symptoms, neuroimaging, neurotransmitters, autonomic and endocrine systems, sleep, memory, and neurodegenerative disorders.

Where is Broca's area located, and what is its primary language function?

Usually the left inferior frontal lobe; speech and language production.

A patient has slow, effortful, nonfluent speech but relatively intact comprehension. What syndrome and brain region are implicated?

Broca's aphasia; damage to the language-dominant inferior frontal cortex, usually the left hemisphere.

Where is Wernicke's area located, and what is its primary language function?

Usually the left posterior temporal cortex; language comprehension.

A patient speaks fluently but meaninglessly and has poor comprehension. What syndrome and brain region are implicated?

Wernicke's aphasia; damage to the language-dominant posterior temporal cortex, usually the left hemisphere.

Broca versus Wernicke: contrast speech fluency and comprehension.

Broca: nonfluent speech with relatively preserved comprehension. Wernicke: fluent but often meaningless speech with impaired comprehension.

What are the frontal lobe's major functions?

Executive functions, planning, inhibition, judgment, voluntary motor control, and speech production.

What are the parietal lobe's major functions?

Somatosensory processing, body awareness, and spatial attention or spatial processing.

What are the temporal lobe's major functions?

Auditory processing, language comprehension, and important aspects of memory.

What is the occipital lobe's primary function?

Visual processing.

Damage to the right parietal lobe most classically produces what attentional deficit?

Left hemispatial neglect.

What brain structure is critical for consolidating new declarative or explicit memories?

The hippocampus.

A patient improves at a motor task but cannot remember practicing it. What structure was likely damaged, and what memory system remains intact?

The hippocampus was likely damaged; procedural or implicit memory remains intact.

Declarative versus procedural memory: what is the core distinction?

Declarative or explicit memory involves consciously recalled facts and events; procedural or implicit memory involves skills and habits.

What is the amygdala's major psychological function?

Processing emotional significance, especially fear and threat, and emotional learning.

What is the cerebellum primarily responsible for?

Coordination, balance, motor timing, and motor learning.

In a typical split-brain patient, information shown only to the left visual field reaches which hemisphere, and why may the person be unable to name it?

It reaches the right hemisphere; language production is usually left lateralized and the severed corpus callosum prevents transfer.

What is the CNS's primary inhibitory neurotransmitter?

GABA.

What is the CNS's primary excitatory neurotransmitter?

Glutamate.

Which neurotransmitter association is classically emphasized in Alzheimer's disease?

Reduced acetylcholine.

Which neurotransmitter and pathway are classically impaired in Parkinson's disease?

Dopamine in the nigrostriatal pathway, due to degeneration of substantia nigra neurons.

Which neurotransmitter do SSRIs directly increase in the synaptic cleft?

Serotonin, by blocking its reuptake transporter.

How do benzodiazepines produce their primary inhibitory effect?

They positively modulate GABA A receptors, increasing GABA's inhibitory action.

What receptor action produces the therapeutic effects and many motor side effects of typical antipsychotics?

Dopamine D2 receptor blockade.

Why can antipsychotics produce parkinsonism?

D2 blockade in the nigrostriatal pathway reduces dopamine signaling and produces Parkinson like motor symptoms.

A patient taking an antipsychotic experiences unbearable internal restlessness and cannot remain seated. What adverse effect is this?

Akathisia.

What feature distinguishes akathisia from many other extrapyramidal symptoms?

It is primarily a subjective inner restlessness and urge to move, often expressed as pacing or inability to sit still.

Soon after starting an antipsychotic, a patient develops sustained painful contractions of the neck or jaw. What adverse effect is this?

Acute dystonia.

What is acute dystonia?

Early onset sustained muscle contractions or spasms that cause abnormal postures, often involving the neck, jaw, eyes, or back.

After long term antipsychotic use, a patient develops repetitive lip smacking and tongue movements. What adverse effect is this?

Tardive dyskinesia.

What is the characteristic timing and movement pattern of tardive dyskinesia?

It usually emerges after prolonged dopamine blocking treatment and involves repetitive involuntary movements, especially of the face, mouth, and tongue.

An antipsychotic patient develops rigidity, bradykinesia, and a resting tremor. What adverse effect is this?

Drug induced parkinsonism.

Differentiate akathisia, acute dystonia, tardive dyskinesia, and drug induced parkinsonism.

Akathisia: inner restlessness. Acute dystonia: early sustained spasms. Tardive dyskinesia: late repetitive involuntary movements, often oral facial. Parkinsonism: rigidity, bradykinesia, and resting tremor.

Which autonomic branch supports fight or flight responses?

The sympathetic nervous system.

Which autonomic branch supports rest and digest functions?

The parasympathetic nervous system.

What major functions are regulated by the hypothalamus?

Homeostasis and motivated or endocrine functions, including temperature, hunger, thirst, circadian rhythms, and pituitary regulation.

Which structure directly links hypothalamic control to much of the endocrine system?

The pituitary gland.

State the HPA axis in order.

Hypothalamus releases CRH; anterior pituitary releases ACTH; adrenal cortex releases cortisol.

Which part of the adrenal gland releases cortisol?

The adrenal cortex.

Which part of the adrenal gland releases epinephrine and norepinephrine?

The adrenal medulla.

Adrenal cortex versus adrenal medulla: contrast their key stress products.

Cortex: cortisol. Medulla: epinephrine and norepinephrine.

Which brain measurement technique directly records scalp electrical activity and has the best temporal resolution?

EEG.

What is EEG's major advantage and disadvantage compared with fMRI?

Excellent millisecond level temporal resolution but relatively poor spatial localization.

Which technique is best for detailed images of brain anatomy or physical structure?

Structural MRI.

Which technique estimates task related brain activity using the BOLD signal?

fMRI.

What does the BOLD signal in fMRI reflect?

Changes in blood oxygenation associated indirectly with neural activity.

MRI versus fMRI: what does each primarily measure?

MRI depicts anatomy or structure; fMRI estimates functional activity through blood oxygenation changes.

Which brain imaging technique uses a radioactive tracer to assess metabolism or receptor activity?

PET.

Match EEG, MRI, fMRI, and PET to their signature features.

EEG: electrical activity and best temporal resolution. MRI: anatomy. fMRI: BOLD based functional activity and good spatial resolution. PET: radioactive tracer and metabolism or receptor activity.

Which sleep stage is characterized by vivid dreaming, rapid eye movements, and muscle atonia?

REM sleep.

Which sleep stage contains sleep spindles and K complexes?

N2 sleep.

Which sleep stage is slow wave sleep and is dominated by delta activity?

N3 sleep.

What is cataplexy?

A sudden loss of muscle tone while consciousness is preserved, often triggered by strong emotion.

Cataplexy is most strongly associated with what disorder?

Narcolepsy.

What neurotransmitter association is classically emphasized in Alzheimer's disease, and what is the key cognitive syndrome?

Reduced acetylcholine; progressive memory and cognitive decline.

What structure and neurotransmitter are classically associated with Parkinson's disease?

Degeneration of the substantia nigra with reduced dopamine in the nigrostriatal pathway.

What movement pattern and inheritance clue point toward Huntington's disease?

Chorea plus cognitive or psychiatric decline with autosomal dominant family history.

What is the inheritance pattern of Huntington's disease?

Autosomal dominant.

Alzheimer's, Parkinson's, and Huntington's: give the signature association for each.

Alzheimer's: acetylcholine loss and progressive dementia. Parkinson's: substantia nigra dopamine loss with rigidity, bradykinesia, and resting tremor. Huntington's: autosomal dominant chorea with cognitive or psychiatric decline