unit 2

NEURON: Basic cell of the NS

Dendrites: Receive incoming signal from Soma

Cell body (includes nucleus)

Axon: AP travels down this

Myelin Sheath: speeds up signal down axon

Terminals: release NTs - send signal onto next neuron

Synapse: gap b/w neurons, releases NT

Action Potential: movement of sodium and potassium ions across a membrane sends an

electrical charge down the axon

All or none law: stimulus must trigger the AP past its threshold, but does not increase

the intensity of the response (flush the toilet)

Refractory period: neuron must rest and reset before it can send another AP (toilet

resets)

Sensory neurons - receive signals

Motor neurons - send signals

Efferent neurons - signal Exits

CENTRAL NS: Brain and spinal cord

PERIPHERALNS: Rest of the NS

Somatic NS: Voluntary movement

Autonomic NS: Involuntary (heart, lungs, etc)

NEUROTRANSMITTERS (NTS): Chemicals released in synaptic gap, received by

neurons

GABA: Major inhibitory NT

GlutamatE: Major Excitatory NT

Dopamine: Reward & movement

Serotonin: Moods and emotion

Acetylcholine (ACh): Memory

Epinephrine & Norepinephrine: sympathetic NS arousal o Endorphins: pain control,

happiness

Oxytocin: love and bonding

Agonist: drug that mimics a NT

Antagonist: drug that blocks a NT

Reuptake: Unused NTs are taken back up into the sending neuron.

SSRIs (selective serotonin reuptake inhibitors) block reuptake - treatment for depression

Hindbrain: oldest part of the brain o Cerebellum - movement, balance

Medulla - vital organs (HR, BP)

Pons - sleep/arousal (Ponzzzzzz)

Midbrain Reticular formation: attention (if you can't pay attent on., Ya R. F'

Forebrain: higher thought processes

Limbic System

Amygdala: emotions, fear

Hippocampus: memory

Thalamus: relay center

Hypothalamus: Reward/pleasure center, eating behaviors

Broca's Area: Inability to produce speech (Broca

- Broken speech)

Wernicke's Area: Inability to comprehend speech (Wernicke's what?)

Cerebral Cortex: outer portion of the brain - higher order thought processes

Occipital Lobe: located in the back of the head - vision

Frontal Lobe: decision making, planning, judgment, movement, personality

Parietal Lobe: located on the top of the head - sensations

Temporal Lobe: located on the sides of the head (temples) - hearing and face

recognition

Somatosensory Cortex: map of our sensory receptors -in parietal lobe

Motor Cortex: map of our motor receptors - located in frontal lobe

Corpus Callosum: bundle of nerves that connects the 2 hemispheres - sometimes

severed in patients with severe seizures - leads to "split-brain patients"

ENDOCRINE SYSTEM: sends hormones throughout the body

Pituitary Gland: Controlled by hypothalamus. release growth hormones

Adrenal Glands: related to sympathetic NS: releases adrenaline

ABSOLUTE THRESHOLD: detection of signal 50% of time

DIFFERENCE THRESHOLD (also called a just noticeable difference (JND) and

follows WEBER'S LAW: two stimuli must differ by a constant minimum proportion.

Sensory Adaptation: diminished sensitivity as a result of constant stimulation

Perceptual Set: tendency to see something as part of a group

- speeds up signal processing Inattentional Blindness: failure to notice something b/c you're so focused on another task (gorilla video)

Cocktail party effect: notice your name across the room when its spoken, when you

weren't previously paying attention