Unit 2: Biological Bases of Behavior psycholgy

Vocabulary flashcards covering neuron anatomy, neural communication, neurotransmitters, nervous and endocrine systems, brain structures, and brain-imaging technologies.

Neuron

Basic nerve cell that receives, processes, and transmits information.

Dendrites

Branch-like fibers that receive incoming messages from other neurons.

Soma (Cell Body)

Portion of neuron that contains the nucleus and processes incoming signals.

Axon

Long fiber that carries an electrical impulse away from the cell body.

Myelin Sheath

Fatty insulation surrounding the axon; speeds neural transmission.

Terminal Buttons

Bulb-like ends of axons that release neurotransmitters into the synapse.

Resting Potential

State when a neuron is negatively charged inside (≈ –70 mV) and inactive.

Action Potential

Brief electrical charge that travels down an axon once threshold is reached.

All-or-None Principle

Action potential fires at full strength or not at all; no partial firing.

Refractory Period

Short time after firing when a neuron cannot fire again.

Neurotransmitter

Chemical messenger released into the synapse to influence other neurons.

Acetylcholine (ACh)

Neurotransmitter for muscle action and memory; low levels linked to Alzheimer’s.

Dopamine

Neurotransmitter for pleasure, reward, and motor control; low = Parkinson’s, high = schizophrenia.

Serotonin

Neurotransmitter regulating mood, hunger, and sleep; low levels linked to depression.

GABA

Major inhibitory neurotransmitter that calms nervous system; low = anxiety or seizures.

Norepinephrine

Neurotransmitter for alertness and arousal; low levels associated with depression.

Endorphins

Natural pain-relief and euphoria neurotransmitters; low levels increase pain.

Central Nervous System (CNS)

Brain and spinal cord; coordinates all bodily functions.

Peripheral Nervous System (PNS)

All nerves outside CNS; connects CNS to limbs and organs.

Somatic Nervous System

PNS subdivision controlling voluntary skeletal muscles.

Autonomic Nervous System

PNS subdivision regulating involuntary functions (organs, glands).

Sympathetic Nervous System

Autonomic branch that triggers "fight or flight" responses.

Parasympathetic Nervous System

Autonomic branch that promotes "rest and digest" functions.

Fight-or-Flight Response

Physiological changes (↑ heart rate, dilated pupils) for emergency action.

Endocrine System

Hormonal communication network sending slow, long-lasting messages.

Pituitary Gland

“Master gland” that regulates growth and controls other endocrine glands.

Adrenal Glands

Endocrine glands that secrete adrenaline/epinephrine in stress situations.

Thyroid Gland

Endocrine gland that regulates metabolism through thyroid hormones.

Hindbrain

Lower brain region containing medulla, pons, and cerebellum.

Medulla

Hindbrain structure controlling vital functions like breathing and heart rate.

Pons

Hindbrain structure involved in sleep and facial expressions.

Reticular Formation

Midbrain network important for attention and arousal.

Cerebellum

Hindbrain structure coordinating balance, posture, and fine motor skills.

Limbic System

Brain system for emotion and memory; includes hippocampus, amygdala, hypothalamus.

Hippocampus

Limbic structure that forms new long-term memories.

Amygdala

Limbic structure processing emotion, especially fear and aggression.

Hypothalamus

Limbic structure regulating hunger, thirst, temperature, and sexual behavior; links nervous and endocrine systems.

Cerebral Cortex

Outer brain layer responsible for complex thinking, perception, and planning.

Frontal Lobe

Cortex region for decision making, personality, and voluntary movement.

Broca’s Area

Region in left frontal lobe responsible for speech production.

Parietal Lobe

Cortex region processing touch, pain, and temperature sensations.

Temporal Lobe

Cortex region for hearing and language comprehension.

Wernicke’s Area

Region in left temporal lobe involved in understanding language.

Occipital Lobe

Cortex region devoted to visual processing.

EEG (Electroencephalogram)

Technique measuring electrical activity (brain waves) on the scalp.

MRI (Magnetic Resonance Imaging)

Imaging method producing detailed pictures of brain structure.

fMRI (Functional MRI)

Technique showing brain activity by tracking blood flow changes.

PET Scan (Positron Emission Tomography)

Imaging that uses glucose tracers to map metabolic brain activity.

CT Scan (Computed Tomography)

X-ray based imaging that shows cross-sectional brain structures.