AP PSYCH - UNIT 2 - The Neural Systems/Brain

AP Psych Semester 1 (1/24/23)

Neuron

Receive sensory input (Afferent), process info & integrate with prior experiences (interneurons). Output guides our actions (Efferent)

Soma

cell body, maintains health of neuron

Dendrites

Receive messages from other cells. Key word: RECEIVE

Axon

Passes message (message are neurotransmitters) away from the cell and to the body, other neurons, muscles, glands.

Action Potential

a neural impulse; a brief electrical charge that travels down an axon

Terminal Buttons/terminal branches

form junctions with other cells

Myelin Sheath

covers the axon of some neurons and helps speed neural impulses

Synapse

Gap between neurons

Glial (glia) cells

support neurons (stimulate growth, repair damage, keep them in place)

Briefly describe the steps of the neural process. Practice this over and over again.

1. Dendrites receive info from other neurons and send info to the soma (cell body).
2. When a neuron is at its resting potential, the soma is polarized (high negative charge). The "message" causes the soma to depolarize (pos. ions come inside, and the cell becomes less negative).
3. If the cell reaches its threshold, an action potential (electric impulse) is fired.
4. Impulse goes down the axon (sodium gates are opening in a chain reaction, allowing more pos. ions to enter... energy/impulse is pushed along the axon).
5. Vesicles are pushed down to the axon terminals where they release neurotransmitters (chemicals) into the synapse.
6. Refactory period occurs where the cell is going back to rest (polarized again). During this time another action potential cannot fire.

Neurotransmitters

chemical (messages) released by the presynaptic neuron

presynaptic

sender neuron

post-synaptic

receiving neuron

Excitatory Postsynaptic Potential (EPSP) vs. Inhibitory Postsynaptic Potential (IPSP)

EPSP: Postsynaptic neuron fires an action potential (depolarized).

IPSP: Postsynaptic neuron does not fire and action potential (polarized).

Reuptake

Neurotransmitters are "recycled" by the presynaptic neuron.

Agonist vs. Antagonist

Agonist: Mimics a neurotransmitter (binds to receptor to activate), prevent reuptake, or increases production/release.

Antagonist: Blocks receptor sites, preventing NT from binding, or decreases production/release

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Acetylcholine

Memory; voluntary muscle movement, used by the parasympathetic nervous system.

Dopamine

Experience of pleasure (reward pathway); initiation of voluntary muscle movement

Norepinephrine

Arousal, alertness, & attention; used by sympathetic nervous system; also associated with mood

Serotonin

Affects mood, appetite, sleep.

GABA

a major inhibitory (dont fire) neurotransmitter; reduce activity of CNS; involved in sleep & arousal.

Glutamate

A major excitatory (fire) neurotransmitter; involved in strengthening neural connections; learning.

Endorphins

Reduce pain; euphoria (runner high)

Peripheral nervous system (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Somatic nervous system

Controls voluntary movements & communication to and from the sense organs - you control these items, they don't "just happen"

Afferent (Sensory) neurons

neurons that carry incoming information from the sensory receptors to the CNS

Efferent (Motor) neurons

neurons that carry outgoing information from the CNS to the PNS and muscles

Autonomic nervous system

controls involuntary (could say automatic but not in the FRQ) functions or items that happen automatically within our body - breathing, heartbeat, digestion, etc.

Parasympathetic

calms the body, conserving its energy and helping keep a state. (returns body to homeostasis). Initiates "rest and digest"

Sympathetic

Physically arouses the body, preparing it to act/react in stressful situations, expending energy. Initiates "fight or flight"

Central Nervous system (CNS)

Consists of the spinal cord and brain, in the center of the body.

Brain

The brain is the neural center of the body, the body's control center.

Spinal Cord

Super highway of nerves the body's needs of transmitting messages to and from the brain.

Reflexes

quick involuntary response/actions controlled by the spinal cord

Electroencephalograph (EEG)

Attach electrodes to scalp, monitor electrical brain waves (brain waves/voltage)

Lesioning

destroying brain tissue (electrode used to burn tissue and disable the structure)

Electrical Stimulation of the Brain (ESB) or Deep Brain Stimulation (DBS)

Stimulate (activate) brain structure with weak electrical currents (sent to an implanted electrode)

Transcranial magnetic stimulation (TMS)

temporary enhancement or depression of activity in a specific area of the brain (using magnetic coil on a small paddle)

Computed tomography

x-ray of brain structure (horizontal slice, angles put together)

Positron Emission Tomography (PET)

Injects a small amount of radioactive chemical activity in different areas of the brain

Magnetic Resonance Imaging (MRI)

uses magnetic fields and radio waves to map out brain structure (shows tissues).

functional magnetic resonance imaging (fMRI)

monitors blood flow, oxygen, etc. in the brain to indentify areas (structure) of high activity (real time, kind of like a movie) when patients are engaged in a certain behavior (mental process).

(HINDBRAIN) Medulla

vital functions (heart rate, blood pressure, breathing). Nerves cross from one side of the body to the opposite side.

(HINDBRAIN) Pons

sleeping & dreaming (REM)

(HINDBRAIN) Cerebellum

Balance and muscle coordination

(FOREBRAIN) reticular formation

a network of cells that control alertness, attention, arousal.

(FOREBRAIN) locus coeruleus

stress and panic responses *(nucleus within the reticular formation)*

(FOREBRAIN) Substantia nigra/striatum

initiation of movement

(MIDBRAIN)Thalamus

"central relay station" for all senses except smell.

(MIDBRAIN) Hypothalamus

biological drives (e.g. hunger, thirst, sex, body temp, sleep.)

Limbic System

emotional responses (Hippocampus & Amygdala)

(LIMBIC SYSTEM) Hippocampus

formation of new memories

(LIMBIC SYSTEM) Amygdala

emotional reactions (especially fear + aggression)

(MIDBRAIN) basal ganglia

important to smooth muscle movement & actions (works with cerebellum). Involved in procedural memory for skills.

corpus callosum

the bundle of nerve fibers connecting the two cerebral hemispheres (left and right hemisphere communication)

association cortex

responsible for thought, memory, and learning in combination with primary parts they surround

\*integration of sensory information

occipital lobe

contains visual cortex: seeing

parietal lobe

contains somatosensory cortex: touch (pressure, temp, pain)

temporal lobe

contains auditory cortex: hearing

frontal lobe

motor cortex: movement

prefrontal cortex:


1. high order thinking + executive functioning (decisions, planning, organization.
2. personality

Mirror neurons

neurons that fire when we watch others preform. Preforming, witnessing, hearing, empathy, skill building through mimicry, and vicarious experiences all apply.

Plasticity

the ability of the brain to strengthen existing neutral connections & form new connections. **Ability to rewire the brain**

Broca's area

located in the left frontal lobe; physical production speech & language

Wernicke's area

located in left temporal lobe; comprehension & interpretation of speech and language.

left hemisphere

controls the right side of the body; speech, language, logic/analysis/math skills.

right hemisphere

Controls left side of the body; nonverbal, creative & artistic, spatial, patterns, & facial recognition, emotion (express & reading others).

Split brain studies

severed/lesioned corpus callosum; right & left hemisphere can no longer communicate

endocrine system

glands that secrete hormones into the bloodstream & absorbed organs & glands throughout the body.

Hormones

chemicals released by the endocrine system into the bloodstream.

pituitary gland

master gland of the endocrine system (in the brain)

Oxytocin

hormone regulating reproductive behaviors (as well as trust, bonding, cooperation, empathy, etc.. the "love hormone", reduces stress)

Chromosomes

strands of DNA that carry genetic info (we have 46)

Zygote

fertilized egg (first 1-2 weeks) - DNA is assembled

Genes

DNA segments (carry hereditary info)

Homozygous

2 of the same genes

Heterozygous

2 genes in a pair are different

Dominant

overrides the other (recessive) gene; expressed in the heterozygous condition.

Recessive

gene that is masked in heterozygous condition; only displayed in a homozygous condition.

Genotype

a person's genetic makeup

Phenotype

"what we see" the way a persons genotype is manifested in observable characteristics.

polygenic inheritance

characteristics influenced by more that one pair of genes (ex: skin color)

monozygotic twins

(identical) 1 fertilized egg that splits (same genotype)

dizygotic twins

(fraternal) separate fertilized eggs (no more alike in genetic makeup than normal siblings)

Genetic mapping

The process of determining the location and chemical sequence of specific genes on specific chromosomes.

Epigenetics

the study of how genetics are controlled by factor other than and individuals DNA sequence. (e.i. how does nurture affect nature.)

Natural Selection

heritable characteristics that provide a survival or reproductive advantage are more likely to be passed down over time.

Fitness

quantitive measurement of ability to survive of reproduce

Adaptation

the ability to change over time, a characteristic that has proved to be advantageous to survival & thus increased prevalence over time.

Conciousness

1. Awareness of external events
2. Awareness of internal sensations
3. Awareness of yourself
4. Awareness of your thoughts

subconscious/preconscious

just below present awareness; can bring into consciousness Ex: memories, knowledge, sensory adaptation/habituation, some physiological processes.

unconscious

completely unaware, cannot access (still impacts us)

states of consciousness

characteristics of awareness at a given point in time

ex: awake/ alert

altered state of consciousness

significant changes in behavior/mental processes

ex: under the influence; sleep deprivation hypnosis, meditation, extreme sickness/high fever

circadian rhythms

What happens during 24 hour cycle

Ex: Sleep/wake cycle, digestion, body temp, blood pressure, attentiveness

suprachiasmatic nucleus

in hypothalamus; regulates the circadian rhythm

entrainment

adjusting to a new cycle (ex. jet lag, night shifts)

EEG

electrodes that measure electrical activity in the brain

EMG

electrodes that measure muscle tension

EOG

electrodes that measure eye movements

Explain the stages of sleep.

Awake & Alert: Beta brain waves

Awake & Resting: Alpha waves

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STAGE ONE: Theta waves; hypnic jerks, light sleep

STAGE TWO: Theta waves dominate; sleep spindles (burst of brain waves) + K-complex waves.

STAGE THREE: Delta waves appear; brain activity, heart rate, etc. decrease.

REPEAT stages 3 then 2, then enter REM