Unit 4 Long version

Central Nervous System (CNS)

Brain and spinal cord; main control center

Peripheral Nervous System (PNS)

Nerves that connect the CNS to the rest of the body

Somatic Nervous System

Controls voluntary skeletal muscle movement

Autonomic Nervous System

Controls involuntary bodily functions

Sympathetic Nervous System

Arouses body for fight-or-flight

Parasympathetic Nervous System

Calms body for rest-and-digest

Neuron

Basic building block of the nervous system

Dendrites

Receive incoming signals

Cell Body (Soma)

Processes information

Axon

Sends electrical impulses away from cell body

Myelin Sheath

Fatty covering that speeds neural transmission

Axon Terminals

Release neurotransmitters

Synapse

Gap between neurons

Action Potential

Electrical signal traveling down a neuron

Polarized

Resting state of neuron (negative inside)

Depolarization

Sodium enters neuron, firing occurs

Repolarization

Potassium leaves neuron, restoring resting state

Long-Term Potentiation (LTP)

Strengthening of synapses through repeated activity

Pruning

Elimination of unused neural connections

Frontal Lobe

Planning, decision-making, movement, personality

Parietal Lobe

Touch and body position

Temporal Lobe

Hearing, memory, language comprehension

Occipital Lobe

Vision

Motor Cortex

Controls voluntary movement

Somatosensory Cortex

Processes touch sensations

Visual Cortex

Processes visual information

Auditory Cortex

Processes sound

Prefrontal Cortex

Judgment, impulse control, planning

Broca's Area

Speech production

Wernicke's Area

Language comprehension

Angular Gyrus

Converts visual words into auditory language

Arcuate Fasciculus

Connects Broca's and Wernicke's areas

Limbic System

Emotion and memory system

Amygdala

Emotion processing, especially fear

Hippocampus

Formation of explicit memories

Hypothalamus

Regulates hunger, thirst, sex, and endocrine system

Pituitary Gland

Master gland controlling hormones

Brain Stem

Controls basic life functions

Medulla

Breathing and heart rate

Pons

Sleep and coordination

Reticular Formation

Arousal and alertness

Thalamus

Sensory relay station (except smell)

Acetylcholine (ACh)

Muscle movement, learning, memory

Dopamine

Reward, motivation, movement

Serotonin

Mood and sleep regulation

Norepinephrine

Alertness and arousal

GABA

Main inhibitory neurotransmitter

Glutamate

Main excitatory neurotransmitter

Endorphins

Pain relief and pleasure

Excitatory Neurotransmitters

Increase likelihood of neuron firing

Inhibitory Neurotransmitters

Decrease likelihood of neuron firing

Agonist

Mimics a neurotransmitter

Antagonist

Blocks a neurotransmitter

SSRI

Blocks serotonin reuptake to improve mood

Endocrine System

Hormone-based communication system (slower than nervous system)

Thyroid Gland

Regulates metabolism

Adrenal Glands

Release stress hormones

Pancreas

Regulates blood sugar with insulin

Pineal Gland

Produces melatonin for sleep

Gonads

Produce sex hormones

EEG

Measures electrical brain activity

CT Scan

X-ray images of brain structure

MRI

Detailed images of brain anatomy

fMRI

Measures brain activity via blood flow

PET Scan

Shows metabolic activity

Corpus Callosum

Connects left and right hemispheres

Split-Brain Study

Shows hemispheres function independently when corpus callosum is cut

Heritability

Degree to which genes explain trait differences

Epigenetics

Environment influences gene expression

Generational Trauma

Trauma effects passed through epigenetic changes

DNA

Genetic material

Gene

Segment of DNA coding for traits

Chromosome

Structure carrying genes

Identical Twins

One fertilized egg splits; 100% same genes

Fraternal Twins

Two eggs fertilized; 50% shared genes

Natural Selection

Traits aiding survival are passed on

Mutation

Random DNA change creating new traits