Human Eye and Brain Function Review

A comprehensive set of vocabulary flashcards focusing on the anatomy of the eye, brain functions, perception principles, sleep cycles, and neurotransmitter systems.

Sclera

Outer white covering of the eye.

Cornea

Transparent part of the eye that focuses light on the retina.

Iris

Muscular ring that controls how much light enters the eye.

Pupil

Hole where light enters the eye.

Lens

Focuses light on the retina.

Retina

Location of sensory receptors and sensory transduction.

Optic Nerve

Transmits visual information from the retina to the brain.

Blind Spot

Region where the optic nerve exits the eye, lacking visual receptors.

Somatosensory Cortex

Brain area that represents body parts with varying degrees of sensitivity.

Homunculus

A visual representation of the body in the sensory or motor cortex.

Gestalt Principles

Principles of perception such as shape and form interpretation.

Closure

The Gestalt principle of perceiving a complete form from incomplete parts.

Proximity

The tendency to group objects that are close to each other.

Ponzo Illusion

An optical illusion that affects perception of size and distance.

Caffeine

A stimulant that acts as an antagonist to adenosine receptors.

Adenosine

An inhibitory neurotransmitter that promotes sleepiness.

Non-REM Sleep

Sleep stages including light sleep (1-2) and deep sleep (3-4).

Delta Waves

Low-frequency brain waves associated with deep sleep.

REM Sleep

Sleep stage characterized by rapid eye movement and vivid dreaming.

Agonist

A substance that enhances the effect of a neurotransmitter.

Antagonist

A substance that blocks the effect of a neurotransmitter.

Reuptake Inhibitor

A substance that prevents the reabsorption of neurotransmitters.

Hypothalamus

Brain region that regulates life-sustaining drives and links nervous and endocrine systems.

Amygdala

Involved in emotional processing, threat detection, and fear responses.

Hippocampus

Critical for memory formation, particularly declarative memories.

Nucleus Accumbens

The brain's reward center associated with pleasure and motivation.

Sympathetic Nervous System

Part of the autonomic nervous system responsible for 'fight or flight' responses.

Parasympathetic Nervous System

Part of the autonomic nervous system that calms the body and conserves energy.

Central Nervous System

Composed of the brain and spinal cord.

Peripheral Nervous System

Includes all nerves outside the central nervous system.

Autonomic Nervous System

Controls involuntary functions and regulates internal organs.

Somatic Nervous System

Controls voluntary movements and relays sensory information.

Hormones

Chemical messengers produced by glands in the body.

Pituitary Gland

The master gland that controls other endocrine glands.

Adrenal Glands

Glands that produce hormones related to stress response.

Thyroid Gland

Regulates metabolism and energy levels.

Serotonin

A neurotransmitter that helps regulate mood, appetite, and sleep.

Dopamine

Involved in reward processing and movement.

Norepinephrine

A neurotransmitter that plays a role in arousal and alertness.

GABA

An inhibitory neurotransmitter that helps regulate excitability in the nervous system.

Histamine

A neurotransmitter involved in wakefulness and alertness.

Sleep Cycle

Progression through different stages of sleep over an 8-hour cycle.

Slow-Wave Sleep

Stage 3 and 4 sleep, characterized by delta waves and restorative functions.

Awake State

Brain activity characterized by high-frequency, desynchronized EEG waves.

Visual Perceptual System

The system responsible for interpreting visual information.

Neurotransmitter

Chemical substance that transmits signals across a synapse.