MCAT Behavioral Sciences Practice Flashcards

Comprehensive MCQ practice flashcards summarizing the key chapters of MCAT Behavioral Sciences (Neurobiology, Psychology, and Sociology).

What was Franz Gall's primary contribution and belief regarding the brain?

He developed the doctrine of phrenology, believing that if a trait was well developed, the corresponding part of the brain would expand, which could be measured by feeling the skull.

What method did Pierre Flourens use to study the brain and what did he discover?

He used extirpation (ablation) on pigeons and rabbits, proving that specific parts of the brain have specific functions and that removing one part weakens the whole brain.

How did William James contribute to the field of psychology?

Known as the founder of American psychology, he studied how the mind adapts to the environment, paving the way for functionalism.

What is the significance of the region discovered by Paul Broca?

Broca discovered that a specific lesion on the left side of the brain (Broca’s area) causes the inability to speak, proving specific impairments are linked to specific brain lesions.

Which researcher was the first to measure the speed of a nerve impulse?

Hermann von Helmholtz, who is credited with transitioning psychology into a quantifiable natural science.

What did Sir Charles Sherrington first infer the existence of?

Synapses (though he mistakenly believed synaptic transmission was an electrical rather than a chemical process).

Distinguish between afferent and efferent neurons.

Afferent neurons (sensory) ascend in the cord toward the brain; efferent neurons (motor) exit the cord on their way to the rest of the body.

What are interneurons and where are they primarily located?

They are the most numerous type of neuron, found between other neurons, located mostly in the brain and spinal cord and linked to reflexive behavior.

How many pairs of spinal and cranial nerves are in the Peripheral Nervous System (PNS)?

There are $31$ pairs of spinal nerves and $12$ pairs of cranial nerves (including the olfactory and optic nerves).

What are the two subdivisions of the Autonomic Nervous System and their primary roles?

The Sympathetic Nervous System (fight or flight) is activated by stress; the Parasympathetic Nervous System (rest and digest) conserves energy and manages digestion.

What are the three layers of the meninges from the skull inward?

$$\text{Dura mater} \rightarrow \text{Arachnoid mater} \rightarrow \text{Pia mater}$$

What are the three primary evolutionary divisions of the brain?

The hindbrain (survival), midbrain (reflexes), and forebrain (complex cognition/emotion).

Describe the five swellings of the mature neural tube.

The telencephalon, diencephalon, mesencephalon, metencephalon, and myelencephalon.

What roles do the medulla oblongata and cerebellum play?

The medulla oblongata regulates vital functions (breathing, heart rate), and the cerebellum maintains posture, balance, and coordinates movements.

What are the primary functions of the superior and inferior colliculi in the midbrain?

The superior colliculus receives visual sensory input; the inferior colliculus receives auditory sensory input.

What are the 'Four Fs' used to remember the functions of the hypothalamus?

Feeding, Fighting, Flight, and Fucking.

Differentiate between the functions of the lateral and ventromedial hypothalamus.

The lateral hypothalamus (LH) triggers hunger/thirst (removal = Lack of Hunger); the ventromedial hypothalamus (VMH) triggers satiety (removal = Very Much Hunger).

What structures comprise the Basal Ganglia and what is their role?

They coordinate muscle movement and maintain steady posture/smooth movements; dysfunction is linked to Parkinson's disease, Schizophrenia, and OCD.

Name the four main lobes of the cerebral cortex and their primary associations.

Frontal (executive function/motor), Parietal (somatosensory/spatial), Occipital (visual), and Temporal (auditory/memory).

What is the difference between contralateral and ipsilateral communication?

Contralateral means one side of the brain communicates with the opposite side of the body; ipsilateral means communication with the same side.

What is the primary inhibitory neurotransmitter in the brain?

GABA (Gamma-aminobutyric acid), which causes hyperpolarization of the postsynaptic membrane.

How do agonists and antagonists differ in pharmacology?

Agonists mimic neurotransmitters by binding to receptors; antagonists block the action of neurotransmitters.

Define the 'nature vs. nurture' debate in psychology.

Nature refers to the influence of inherited traits (genetics); nurture refers to the influence of environmental factors.

What is the Babinski reflex in infants?

An primitive reflex where the toes spread apart automatically when the sole of the foot is stimulated.

Distinguish between sensation and perception.

Sensation is the raw conversion of physical stimuli into electrical signals (PNS to CNS); perception is the processing of those signals to make sense of their significance (CNS).

What is Weber's Law?

The principle that difference thresholds are proportional to the magnitude of the original stimulus; the just-noticeable difference (jnd) is calculated as a percentage: $\frac{\text{change in stimulus}}{\text{original stimulus}}$.

List the four possible outcomes in Signal Detection Theory.

Hit (signal present and perceived), Miss (signal present not perceived), False Alarm (signal absent but perceived), and Correct Negative (no signal, none perceived).

What are the two muscles of the iris and how are they controlled?

The dilator pupillae (sympathetic control) and the constrictor pupillae (parasympathetic control).

Differentiate between rods and cones in the retina.

Cones are for color and fine detail ($6$ million); rods are for low light and contain rhodopsin ($120$ million).

What is the 'Place Theory' of hearing?

The location of a hair cell on the basilar membrane determines the perception of pitch: high frequency vibrates near the oval window, low frequency near the apex.

Describe the difference between bottom-up and top-down processing.

Bottom-up (data-driven) combines individual stimuli to create an image; top-down (conceptually driven) uses memories and expectations to recognize the whole object first.

What is habituation and dishabituation?

Habituation is a decrease in response after repeated exposure to a stimulus; dishabituation is the recovery of a response to a stimulus after a change in conditions.

In classical conditioning, what is generalization?

A broadening effect where a stimulus similar to the conditioned stimulus produces the conditioned response.

Define the four types of reinforcement schedules in operant conditioning.

Fixed-ratio (set number), Variable-ratio (varying number - fastest learning), Fixed-interval (set time), and Variable-interval (varying time).

What are mirror neurons?

Neurons in the frontal and parietal lobes that fire both when an individual performs an action and when they observe someone else performing it.

Distinguish between explicit and implicit long-term memory.

Explicit (declarative) requires conscious recall of facts (semantic) and experiences (episodic); implicit (nondeclarative) involves skills and habits (procedural).

What is the serial-position effect?

The tendency to remember the first few items (primacy effect) and last few items (recency effect) on a list better than the middle items.

What is Piaget's sensorimotor stage and what ends it?

From birth to age $2$, children learn to coordinate sensory/motor input; it ends with the development of object permanence.

Define the four patterns of brain waves during sleep and alertness.

Beta (alert/concentrated), Alpha (awake/relaxing), Theta (Stage 1 and 2 sleep), and Delta (Stage 3/Slow-wave sleep).

What is the Whorfian (Linguistic Relativity) hypothesis?

The proposal that our perception of reality is determined by the context of our language.

Describe the Yerkes-Dodson Law.

A bell-shaped function stating that performance is optimal at an intermediate level of arousal, and poor at high or low extremes.

What are the three stages of the General Adaptation Syndrome (GAS)?

$$\text{Alarm} \rightarrow \text{Resistance} \rightarrow \text{Exhaustion}$$

Differentiate between an internal and external locus of control.

Internal locus of control means viewing oneself as in control of one's fate; external believes luck or outside influences cause events.

List Freud's five stages of psychosexual development.

Oral, Anal, Phallic, Latency, and Genital.

What is the main diagnostic tool for psychological disorders in the U.S.?

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5).

Distinguish between positive and negative symptoms of schizophrenia.

Positive symptoms add behaviors/thoughts (delusions, hallucinations); negative symptoms involve the absence of normal behavior (disturbance of affect, avolition).

What characterizes a Personality Disorder in Cluster B?

Dramatic, emotional, or erratic behavior, including Antisocial, Borderline, Histrionic, and Narcissistic disorders.

What is the biological hallmark of Parkinson’s Disease?

Decreased dopamine production in the substantia nigra, affecting the function of the basal ganglia.

Define groupthink.

A social phenomenon where the desire for harmony/conformity leads to poor decision-making by ignoring outside viewpoints.

What is the difference between incidence and prevalence in epidemiology?

Incidence counts new cases ($\frac{\text{new cases}}{\text{pop at risk} \times \text{time}}$), whereas prevalence counts total cases ($\frac{\text{total cases}}{\text{total population} \times \text{time}}$).