AP Psych Unit 2

Neurons

Individual cells in the nervous system that receive, integrate, and transmit information.

Soma/Cell Body

contains the cell nucleus and much of the chemical machinery common to most cells

Dendrites

Branchlike parts of a neuron that are specialized to receive information.

Axon

Long fiber that carries impulses away from the cell body of a neuron and transmits signals to other neurons

Myelin Sheath

insulating material that encases some axons

Terminal Button

small knobs that secrete neurotransmitters

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons and activate other neurons

Resting Potential

the state of the neuron when not firing a neural impulse/inactive, a stable negative charge (-70mV)

Action Potential

A brief shift in a neuron's electrical charge positively that travels along an axon.

Absolute Refectory Period

minimum length of time before another action potential can begin (1-2 milliseconds)

All or None Law

neurons must fire or not fire, all action potentials are equal in strength (but not rate)

Presynaptic Neuron

neuron that sends the signal (neural impulse) to another neurons

Postsynaptic Neuron

neuron that receives the signal (neural impulse)

Postsynaptic Potential (PSP)

a voltage change at a receptor site on a postsynaptic cell membrane, does not follow All or None Law (varies in charge/strength)

Inhibitory PSP

a negative voltage shift that decreases the likelihood that the postsynaptic neuron will fire action potentials

Excitatory PSP

a positive voltage shift that increases the likelihood that the postsynaptic neuron will fire action potentials

Reuptake

the reabsorption of inactive neurotransmitters by a presynaptic neuron's terminal button

Synaptic Pruning

the elimination of old or less-active synapses

Acetylcholine (ACh)

neurotransmitter
-involved in motor neurons
-contributes to attention, arousal, memory, learning, movement and sleep
-excess: depression
-deficit: dementia
-agonist: nicotine

Dopamine (DA)

neurotransmitter

• involved in voluntary movement, attention, alertness

• known as the reward pathway -excess: schizophrenia -deficit: parkinson's disease -cocaine increase dopamine synapse activity

Norepinephrine(NE) / Epinephrine

neurotransmitter

• contributes to change in mood, arousal, fight or flight response

• cocaine elevates synapse activity

• excess: high blood pressure, schizophrenia

• deficit: depression

Serotonin

neurotransmitter

• regulates sleep, wakefulness, eating, aggression, mood regulation -deficit: depression, anxiety disorders, OCD

• antagonist: LSD

• Prozac & SSRIS stop serotonin reuptake

GABA

neurotransmitter

• tends to work as an inhibitor

• regulates anxiety, sleep and arousal

• agonist: valium, anti-anxiety drugs, alcohol

• excess: seizures, insomnia

• deficit: anxiety disorders

Endorphins

neurotransmitter

• contributes to pain relief, stress response and eating

• agonist: opiates (heroin & morphine)

• deficit: addiction

Agonist

A chemical that mimics the action of a neurotransmitter.

Antagonist

chemical that blocks receptor sites

Central Nervous System (CNS)

brain and spinal cord

Peripheral Nervous System (PNS)

all nerves outside of brain and spinal cord

Autonomic Nervous System (ANS)

nerves that connect to the heart, blood vessels, smooth muscles and glands (automatic, involuntary functions)

Somatic Nervous System

nerves that connect to voluntary skeletal muscles and to sensory receptors (movement and senses)

Sympathetic Division

branch of Autonomic Nervous System (ANS) that uses the body's resources for emergencies, division in flight or flight

Parasympathetic Division

branch of Autonomic Nervous System (ANS) that conserves the body's resources

Fight or Flight Response

autonomic, bodily and emotional response to either fight or flee a threat

Afferent Nerve Fibers

axons carry info from the Peripheral Nervous System (PNS) to Central Nervous System (CNS)

Efferent Nerve Fibers

axons carry info from the Central Nervous System (CNS) to Peripheral Nervous System (PNS)

Spinal Cord

connects brain to the rest of the body through the Peripheral Nervous System (PNS)

Cerebrospinal Fluid (CSF)

fluid that cushions and protects the brain

Lesioning

destroying a piece of the brain

Electrical Stimulation of the Brain (ESB)

Sending a weak electric current into a brain structure to stimulate (activate) it.

James Olds' research on pleasure centers

rats would press a lever (hundreds of thousands of times) to stimulate the pleasure center of the brain (aka dopamine)

Computerized Tomography scan (CT)

computer enhanced x-ray of brain structure

magnetic resonance imaging scan (MRI)

use of magnetic fields, radio waves and computerized enhancements to map the brain, better at mapping the brain than CTs

Position Emission Tomography scans (PET)

use of radioactive markers to map the chemical activity in the brain

functional magnetic resonance imaging scans (fMRI)

new variations of MRI scans that monitor oxygen & blood consumption in the brain, and activity over time

brainstem

responsible for automatic survival functions, connects the spinal cord to the brain

Hindbrain

-lowest part of the brainstem
-medulla, pons, cerebellum

Medulla

-part of hindbrain
-attached to spinal cord
-controls unconscious essential functions, breathing, heartbeat, etc.

Pons

-part of hindbrain
-fibers that connect brainstem to the cerebellum

Cerebellum

-part of hindbrain
-largest structure next to the back of the brain stem
-controls movement coordination, physical balance and fine motor skills

Reticular Formation

-between hindbrain and midbrain
-contributes to controlling muscle reflexes, breathing and pain perception

Forebrain

-largest, most complex region of the brain
-cerebrum, cerebral cortex, thalamus, hypothalamus, limbic system

Midbrain

-between hindbrain and forebrain
-helps with sensory processes, voluntary movement and releasing dopamine

Cerebrum

-helps with complex thought
-part of forebrain

Cerebral Cortex

-wrinkled surface of the cerebrum
-part of forebrain

Thalamus

-part of forebrain
-cluster of cells/axons
-help pass sensory info (besides smell) to the cerebral cortex, integrates info from senses

Hypothalamus

-part of forebrain
-cluster of cells
-regulate basic biological needs and controls the Autonomic Nervous System (ANS)
-supports endocrine system
- four Fs: fight, flee, feed, fornicate

Limbic System

-part of forebrain
-loosely connected network of structures, including parts of the thalamus, hypothalamus, hippocampus, amygalda, etc.
-helps memory processes, experience emotion, contains pleasure centers

Hippocampus

-helps in transferring short term to long term memory
-forebrain

Amygalda

-helps in basic emotional responses
-forebrain

cerbral hemispheres

right and left halves/hemispheres of the cerebrum

corpus callosum

connects the two cerebral hemispheres

Lobes

the different regions into which the cerebrum is divided

Occipital Lobe

• includes visual cortex, which helps with visual signals and visual processing

• includes visual processing

Parietal Lobe

• includes somatosensory cortex, which helps with sense of touch

• registers touch, integrating input and monitoring the body's position

• includes sense of touch, feeling of temperature and pain, causing phantom limb syndrome, processing info from body

Temporal Lobe

• includes auditory cortex, which helps with auditory processing

• helps with speech and language, hearing, speaking, verbal language

• includes wernicke's area, which helps with understanding language

Frontal Lobe

-largest lobe

• includes motor cortex, which helps with controlling muscle movement

• includes prefontal cortex, which helps with reasoning, planning, paying attention, decision making, etc.

• includes broca's area

Mirror Neurons

neurons that are activated by performing an action or by seeing another monkey or person perform the same action

Prefrontal Cortex

very large, contributes to decision making and self control, reasoning, planning, decision making, impulse control

Brain Plasticity

-parts of the brain are anatomically flexible
-aspects of experience changes brain structure
-damage of sensory pathways/brain tissue leads to neural reorganization
- adult brains can generate new neurons

Neurogenesis

the formation of new neurons

Right Brain

controls left side of body, non verbal expressions, spatial skills, creativity

Left Brain

controls right side of body, language, math, logic, analytics

Robert Sperry's and Michael Gazzaniga's Research

cut and removed the corpus callosum to try and find treatment for epilepsy, found that it reduced seizures, but transfer of information between the two brains is lost

Wernicke's Area

• temporal lobe

• comprehension of language

Broca's Area

• frontal lobe

• production of speech

Homunculus Brain Map

a map of brain areas showing what parts of the brain control parts of the body

Electroencephalogram (EEG) scan

monitors electrical activity of the brain (brain waves)

ventricles

cavities within the brain that store cerebrospinal fluid (csf)

Motor Cortex

helps with precise, fine muscle movement

Somatosensory Cortex

helps control sensory info

Auditory Cortex

Visual Cortex

Endocrine System

the glands that secrete hormones into the bloodstream that help control bodily functions, heavily supported by the hypothalamus

Hormones

chemical substances released by the endocrine systems (last long term and through the bloodstream, unlike neurotransmitters)

pituitary gland

pea sized, releases variety of hormones, stimulates actions of other endocrine glands (called the master gland), part of endocrine system and CNS

Oxytocin

released by pituitary gland, controls reproductive behavior

Pineal Gland

part of endocrine system, secretes melatonin, helps circadian rhythm

Thyroid Gland

part of endocrine system, produces hormones that regulate metabolism, body heat, and bone growth

Liver

supports endocrine system, helps with bloodwork

adrenal glands

glands that help the body recover from stress and respond to emergencies, secretes adrenaline

Pancreas

part of endocrine system, Regulates the level of sugar in the blood, secretes insulin, near the liver

Ovary (Gonads)

part of endocrine system, helps with reproductive health and fertility, secretes estrogen

Testis/Testicles (Gonads)

helps with reproductive health and fertility, secretes testosterone

Chromosones

threadlike strands of DNA molecules that carry genetic info 46 choromsones in cells, 23 from each parent

Genes

DNA segments that pass on hereditary info

Polygenic Traits

characteristics influenced by more than one part of genes

Family studies

researchers assess hereditary influence by examining blood relatives to see how closely they all have one specific trait, correlative not causative, easily confounded

Twin Studies

hereditary influence is assessed by comparing identical/fraternal twins on a specific trait, more accurate than family studies

Monozygotic Twins

one egg splits, identical twins, 100% identical genes

Dizygotic Twins

two eggs are fertilized at the same time, fraternal twins, 50% identical genes