AP Psych Modules 5-7

Plasticity

the brain’s ability to adapt and repair itself

Glial Cells

Protects neurons and myelin

Helps with learning, thinking, memory

Supplies nutrients

Cleans up ions and neurotransmitters

Axon

transmits messages from its branches to other neurons or muscles/glands

Nucleus

decides whether to fire neuron or not

Myelin Sheath

fatty tissue that protects neuron and axons; allows faster transmission of neural impulses

Dendrite

receives messages from other neurons or muscles/glands

Afferent (Sensory) Neurons

transmits signals from sensory organs to central nervous system

Interneurons

neurons in the brain that send messages to other neurons (most common)

Efferent (Motor) Neurons

Transmits signals from central nervous system to muscles

Neurotransmitters

Chemical messengers that cross gaps between synapses to send specific messages/signals

Agonists

molecules that increase the activity of a neurotransmitter

Antagonist

molecules that decreases the activity of a neurotransmitter

Hormones

Chemical messengers created by endocrine glands that are spread throughout the bloodstream

Acetylcholine (ACH)

Controls muscle contractions

Excitatory

Correlated with Alzheimer's

Dopamine

• Reward center

• Excitatory

• Correlated with Parkinson's and Schizophrenia

Noradrenaline/Norepinephrine

• Fight/flight response

• Excitatory

• Adrenaline

Serotonin

• Inhibitory

• Imbalance of serotonin is correlated with excess eating, depression, alcoholism

GABA

• Inhibitory

• Produces calming effect

• Can cause anxiety with low levels

Endorphins

• Inhibitory

• Natural “opiate-like”

• Controls pain → pleasure

• Blocks pain receptors

Inhibitory

decrease the likelihood that the neuron will fire

Excitatory

increases the likelihood that the neuron will fire

Action potential

neural impulse that has a short electrical charge, which travels down the axon (+30 mV)

Resting Potential/State

when there are more negative sodium ions inside the axon and positive potassium ions outside the axon (-70 mV) → this is how axons are usually found

Depolarization

negative sodium ions are pushed out the axon and positive potassium ions are pushed inside → occurs during firing of neuron

Repolarization

process where negative sodium ions are pushed back in the axon and positive potassium is pushed out → returns to resting potential/state

Refractory period

period of inactivity after a neuron has been charged

Absolute refractory period

the neuron will only fire once the axon is returned to the resting state completely

Relative refractory period

the neuron will fire before the axon has reached resting state, but has still crossed some level of repolarization

Threshold

the amount of stimulation needed to start a neural impulse

Excitatory signals

causes the next neuron to fire

Inhibitory signals

does not cause next neuron to fire

All-or-none response

neuron’s response of firing or not firing

Reuptake

reabsorption of a neurotransmitter by a sending neuron

Central nervous system

brain and spinal cord

Peripheral nervous system

sensory and motor neurons that connect the central nervous system to the rest of the body

Somatic nervous system

a part of the peripheral nervous system that control skeletal muscles (voluntary)

Autonomic nervous system

a part of the peripheral nervous system that controls glands and muscles of internal organs (involuntary)

Sympathetic nervous system

a division of the autonomic nervous system that arouses the body and gives it energy

Parasympathetic nervous system

a division of the autonomic nervous system that calms the body and conserves energy

Endocrine System

consists of glands and chemical signals (hormones) that travel slowly throughout the body through the bloodstream

Adrenal Gland

makes the body alert during stress

Pituitary gland

controlled by the hypothalamus and regulates the growth of other endocrine glands

Frontal Lobe

Controls the following:

• Emotional control

• Planning for the future

• Personality

• Attention

Motor Cortex

controls all muscle movements and works with somatosensory cortex

Broca’s Area

controls speech and writing

Parietal Lobe

Responsible for spatial tasks

Somatosensory Cortex

responsible for all body sensations, including pain/pleasure

Occipital Lobe

Controls and processes visual stimuli

Primary Visual Cortex

raw images of what you see visually

Visual Association Area

perception; processing of what you see

Temporal Lobe

Located by the ears; controls hearing

Primary Auditory Cortex

hears the sounds

Auditory Association Areas

understand and interprets the sounds

Wernicke’s Area

language comprehension

Hindbrain

Responsible for automatic survival functions

Pons

Coordinates movements and regulates sleep

Medulla

Controls breathing and heart rate

Cerebellum

Controls balance and coordination

Reticular Formation

A neuron network that filters stimuli coming from the spinal cord to the thalamus. Also controls arousal

Brainstem

Oldest part of the brain

Controls automatic survival functions of the body

Cerebrum

Includes all the lobes

Controls muscle function, speech, thought, emotion, reading, writing, and learning

Largest part of the brain

Made up of white and gray matter

Prefrontal Cortex

Part of frontal lobe

Part of the brain responsible for reasoning, problem solving, impulse-control, creativity, and perseverance

Corpus Callosum

separates the left and right hemispheres of the brain

transmits messages between these two hemispheres

Left Hemisphere

controls right side of body

right field of vision

speech/language

analytical

abstract thinking

Right Hemisphere

controls left side of body

left field of vision

creativity

imagination

spatial thinking

Limbic System

Controls behavioral and emotional responses

Thalamus

Receives sensory information (besides taste)

Filters the information coming through the Reticular Formation

Hippocampus

Memories are formed here (not stored)

Amygdala

Controls emotions

Allows for the ability to read facial expressions

Controls fear and aggression

Fight or Flight

Hypothalamus

controls pituitary gland, primitive emotions, hunger/thirst, temperature regulation

Lesions

Disruptions of the brain tissues

Stimulation

Using electrodes to study the brain

Electroencephalograph (EEG)

Electrodes on the scalp track brain activity in certain regions

CAT scan

a generally clear picture is created by taking many x-rays at different angles to see the brain

MRI

a technique that uses magnetic fields and radio waves to produce computer generated images of soft tissue

PET Scan

visually displays brain activity and detects where a radioactive form of glucose goes while the brain performs a given task

fMRI

a technique for revealing blood flow and therefore brain activity by comparing successive MRI scans