Psychology Review: Brain Anatomy, Sleep Stages, and Research Methods

A comprehensive vocabulary review of key terminology covering brain anatomy, hemisphere functions, language centers, sleep stages, sleep disorders, dream theories, and basic experimental variables.

Brain Stem

The structure comprising the brain and the spinal cord.

Medulla

Part of the brainstem responsible for automatic body functions, such as regulating the heart and lungs.

Reticular Activating System (RAS)

Brain structure responsible for controlling alertness, arousal, and attention.

Cerebellum

Part of the brain responsible for maintaining balance, coordination, and movement.

Thalamus

The sensory relay station of the brain that receives sensory information and transmits it to the appropriate cortex.

Hypothalamus

Brain structure that maintains homeostasis (body calmness) and regulates food, fight, flight, Fahrenheit (body temperature), and arousal.

Pituitary Gland

Gland responsible for regulating hormones throughout the body.

Hippocampus

Brain structure responsible for storing and enabling the formation of new memories.

Amygdala

Brain structure responsible for processing emotions, primarily anger and fear.

Corpus Callosum

Structure that connects the left and right hemispheres of the brain.

Occipital Lobe

Lobe of the brain located at the back of the head that is responsible for visual processing.

Temporal Lobe

Lobe located on the sides of the head that processes auditory information.

Parietal Lobe

Lobe of the brain responsible for processing physical sensations.

Frontal Lobe

Lobe of the brain responsible for personality and higher-order thinking.

Somatosensory Cortex

Region of the brain that processes physical sensory sensations, such as touch and pain.

Motor Cortex

Region of the brain responsible for initiating voluntary muscle movements.

Broca's Aphasia

Condition where a person can understand language but cannot physically produce speech.

Wernicke's Aphasia

Condition where a person can speak fluently with normal rhythm, but produces largely meaningless sentences (word salad) and struggles to understand language.

Plasticity

The brain's ability to adapt and form new connections, especially after suffering a traumatic brain injury.

EEG

Brain imaging technique used to measure electrical activity in the brain.

fMRI

Brain imaging technique used to measure brain activity by tracking blood flow.

Lesioning

The process of damaging, cutting, or removing specific parts of the brain to study the resulting changes in behavior.

Split-Brain Research

Studies involving the severing of the corpus callosum to examine functional differences between the left and right hemispheres.

Left Hemisphere

Hemisphere of the brain associated with language, speech production, and analytical processing.

Right Hemisphere

Hemisphere of the brain associated with visual-spatial skills, motor controls, and creative processing.

Contralateral Control

Principle stating that each hemisphere of the brain controls and receives sensory input from the opposite side of the body.

Circadian Rhythm

The internal 24-hour biological clock that regulates body processes, primarily the sleep-wake cycle.

Jet Lag

Sleep disruption that occurs when an individual's internal clock does not align with the current physical time zone.

Shift Work

Working unusual hours (such as late night shifts) that disrupts an individual's natural sleep schedule.

NREM Stage 1

Initial stage of light sleep transitioning from wakefulness, characterized by hypnagogic sensations like muscle contractions.

NREM Stage 2

Stage marking the onset of true sleep, characterized by theta waves, sleep spindles, and K-complexes.

NREM Stage 3

Deep sleep stage characterized by delta waves, physical body restoration, memory consolidation, and sleepwalking.

Somnambulism

The formal term for sleepwalking.

REM Sleep

Sleep stage characterized by beta-like waves, high brain activity, vivid dreams, and temporary body paralysis; also called paradoxical sleep.

REM Rebound

The phenomenon of experiencing increased REM sleep to catch up after being sleep deprived.

Memory Consolidation Theory

Theory that sleep aids in strengthening, organizing, and storing memories learned throughout the day.

Insomnia

Sleep disorder characterized by persistent difficulty falling or staying asleep.

Narcolepsy

Sleep disorder characterized by sudden and uncontrollable sleep episodes.

Sleep Apnea

Sleep disorder in which a person repeatedly stops breathing while sleeping.

REM Sleep Behavior Disorder

Sleep disorder where normal muscle paralysis during REM sleep is absent, causing the person to physically act out their dreams.

Activation-Synthesis Theory

Dream theory proposing that dreams are created by the brain attempting to synthesize and make sense of random neural activity during sleep.

Mean

The arithmetic average calculated from a set of numbers.

Median

The middle value in a dataset when the numbers are arranged from least to greatest.

Mode

The specific value or number that appears most frequently in a dataset.

Range

The numerical difference calculated by subtracting the lowest value from the highest value in a dataset.

Independent Variable

The specific variable in an experiment that is directly manipulated or changed by the experimenter.

Dependent Variable

The measured outcome in an experiment that changes in response to manipulations made to the independent variable.