AP Psychology Unit 1: Brain Structure, Neurotransmitters, and Nervous System

Cell Body

Also known as the "Soma", this is the headquarters of the neuron. It's where the decisions are made- whether messages are passed on.

Dendrites

They receive messages from other cells and give those messages to the cell body.

Axon

They are like tubes and take messages from the cell body to other neurons using electrical (inside neurons) and chemical (between neurons) reactions.

Myelin Sheath

They cover the axons of neurons to keep from messages leaking out.

Terminal Button

Branches at the end of the axon that have chemicals (i.e. dopamine) waiting to be released by a message.

Synaptic Gap

The gap in between neurons.

Neurotransmitters

They are there to regulate body reactions. They can be excitatory (stimulate brain) or inhibitory (relax brain).

Reuptake

More neurotransmitters than necessary are sent to bond with the dendrite receptor site. The extra neurotransmitters are sent back to the terminal branch in a process called ________.

Glial Cells

These assist the neuron by rebuilding the glial sheath.

Action potential

The excitatory neurotransmitters reach the threshold, so the message is passed along. The ions start to mix with Na+ entering, and K leaving the tube.

Resting potential

There are no messages/activity, the neuron is chill. Ions are polarized, Na+ is outside (positive) and K is inside (negative).

Refractory period

The axon is being reset and Na+ leaves the tube and K enters.

Threshold

When excitatory neurotransmitters reach a certain amount and cause a reaction.

All or Nothing Response

After the neurotransmitters reach the threshold, the same reaction happens. The message is not intensified based on the amount of neurotransmitters.

ACh

Excitatory. It deals with muscle movement (mainly skeletal muscles-more voluntary) and memory. Low level of _______ is associated with Alzheimer's.

Dopamine

Excitatory. It's like the joy leading up to an event- it's highly addictive, and it's how the body gets you to do things. Low levels of _______ are associated with Parkinson's (tremors) and ADHD (trouble focusing).

Serotonin

Inhibitory. It's the bliss/relaxation you feel while doing something and it deals with mood. Low levels are associated with clinical depression.

Norepinephrine

Excitatory. It deals with alertness and energy and helps wake you up. Low levels are also tied to clinical depression.

GABA

Inhibitory- main. It relaxes you. Low levels are associated with anxiety, insomnia, seizures, and mania.

Glutamate

Excitatory- main. It deals with memory and energy. It's the most abundant neurotransmitter.

Substance P

Excitatory. Causes you to feel pain. Pain is important because it causes you to notice when you're hurt and do something about it.

Endorphine

Inhibitory.

Pain

Important because it causes you to notice when you're hurt and do something about it.

Agonists

They cause there to be extra 'keys' in the system, amplifying the affected neurotransmitter.

Direct agonists

Imitate neurotransmitters and flood the system.

Indirect agonists

Reuptake inhibitors, so the 'keys' can't go back and therefore stay in the system.

Antagonists

Block the 'lock' or receptor site so the 'key' can't fit in, nullifying that neurotransmitter.

Phrenology

How people studied the brain/mind before psychology by feeling and mapping the shape of the head.

Gall

The most famous phrenologist.

Phineas Gage

His injury helped kick start the invention of modern psychology by showing the effects of brain injury on personality.

fMRI

Deals with structure and function, providing imaging by tracking oxygen.

MRI

Deals with structure, providing imaging by tracing where in your brain the blood flows.

CAT/CT scans

Deal with structure by taking multiple x-rays of your brain.

PET scans

Deal with function by having the patient drink radioactive glucose and looking at where the brain lights up.

EEG

Maps out electrical activity by sticking electrodes to your head, mostly used for sleep research and verifying disorders.

MEG

Shows how parts of the brain work together.

Central Nervous System

Comprises the brain and spinal cord.

Peripheral Nervous System

Deals with all other parts of the nervous system, handling everything you feel.

Somatic Nervous System

Handles voluntary skeletal movements that you can control.

Autonomic Nervous System

Deals with self-regulated actions, such as heart beating and digestion.

Sympathetic Nervous System

Arousing system that deals with fight or flight reactions.

Parasympathetic Nervous System

Calming system that deals with returning to normal after being stressed.

Afferent(sensory) neurons

Neurons that send data from the body part to the spinal cord.

Efferent(motor) neurons

Neurons that send data from the spinal cord to the body part.

Interneurons

Act as middlemen for messages in the spinal cord/brain.

ALS

Destroys motor neurons, leading to paralysis and eventual death.

Reflexes

Bypass the interneurons due to certain stimuli.

Multiple Sclerosis

Damages myelin sheath, causing messages to be partially lost.

Myasthenia Gravis

Affects transmission of axon, causing issues with facial muscle movement.

Lesion

Purposefully damaging the brain for research.