AP Psych Unit 2 - Biopsychology

Most AP Textbook terms and class notes

Central Nervous System

Central Nervous System

The nervous system composed of the brain & spinal cord

Brain

a part of the central nervous system

• powered by bioelectrical & biochemical energy

• only about 15-20% developed at birth

• operates through a network of subsystems connected by electrical circuits

Spinal Cord

part of the central nervous system

• physically bridges the brain to the body

Reflex arc (spinal cord)

• provides protection & physical damage control

• in cases of physical trauma to the body, the spinal cord can supersede the brain

Afferent neurons

• sends impulses to the spinal cord which triggers an automatic muscle contraction

• once out of harms way, the brain sends sensory signals to calm down

Peripheral Nervous System

A nervous system composed of nerve receptor networks, eyes, ears, etc.

Somatic Nervous System

(under the PNS) controls voluntary body movements

Autonomic Nervous System

(under PNS) controls involuntary movements and body operations

Sympathetic Nervous System

(under ANS)

• Prepares body for physical & emotional stress

• fight, flight, freeze

• epinephrine / adrenaline, acetylcholine

Parasympathetic Nervous System

(under ANS)

• relaxes body after stress

• calms body back to homeostasis

• norepinephrine / noradrenaline

Sensory neurons

• also called afferent neurons

• transmits sensory information from sensory receptors & relays them through the spinal cord to the brain

• takes 80 milliseconds for the nervous system to respond to stimuli

Motor neurons

• also called efferent neurons

• transmits neural signals from the brain, through the spinal cord, to muscle groups

Interneurons

specialized nerve cells within the brain and spinal cord that provide the structure for the transmission of energy (action potential)

Humans are born with over

300 billion neurons but by the end of the first year, we only have ±100 billion neurons

Glial Cells (Astrocyte)

• responsible for replenishing nutrients & biochemicals

• removal of cellular waste

• crystalizes axons with myelin

• pruning & decomposition of unused neuron

Action Potential

bioelectrical process of neuron cells sending & receiving neural impulses throughout the nervous system; activated by polarization of potassium & sodium electrons

Axons

“extension cords” that carry neural signals (bioelectrical currents) from the nucleus of the cell body to a receiving neuron

Myelin

a sheath of fatty, waxy plaque that surrounds and protects axons; accelerates neural processing speed of a circuit and minimizes energy loss.

Rehearsal of an action promotes

a thicker coating of myelin which means quicker processing and response time

Factors of intelligence

• speed & efficiency of energy transmission

• neuroplasticity

Neuroplasticity

the flexibility & responsiveness to create new circuits

Axon terminals

Porous membranes at the tip of axons that house sacs of neural transmitters that release proper types and amounts of chemicals specified by electrical shocks

Synapse (gap/cleft)

the space or gap separating physical connection between neurons (this creates an open circuit)

Neurotransmitters

biochemical molecules that are released from one neuron & are absorbed by the receiving neuron

Dendrites

leafy fibers branching out from neural soma that contain neurotransmitter receptor sites; they receive biochemical signals from presynaptic axon terminals and relay signals onto nucleus of receiving neuron

Reuptake

reabsorption of excess amount of neurotransmitters from the presynaptic neuron following an action potential firing

Reuptake inhibitors

chemical substances that inhibit natural reuptake and increase neurotransmitter functionality

Serotonin

• Neurotransmitter

• regulates mood & emotion

• helps regulate circadian rhythm cycles

• imbalance can lead to mood + anxiety disorder

Dopamine

• Neurotransmitter

• promotes fluid muscle movements

• enables cognitive focus and mental concentration

• stimulates brain’s reward & pleasure center

• imbalances lead to ADHD/ADD, schizophrenia, and parkenson’s disease

Epinephrine

• Neurotransmitter

• Prepares emotional & physical stress responses

• released upon activation of sympathetic nervous system

• physical alertness, blood circulation

• waking up from sleep

Norepinephrine

• Neurotransmitter

• depresses and tranquilizes the body after stressful situations

• allows body to stay asleep

Melatonin

• Neurotransmitter

• works with serotonin to regulate sleep cycle

• sleep inducer

Acetylcholine

• Neurotransmitter

• aids in memory encoding and information processing

• promotes cognitive learning

• released in large quantities during times of SNS stress response

Substance P

• Neurotransmitter

• physical pain sensation

Endorphins

• Neurotransmitter

• opiate-based, biologically produces molecules

• body’s natural pain surpressors

GABA

• Neurotransmitter

• regulates impulsivity, inhibition

Oxytocin

• Neurotransmitter

• promotes bonds of social attachment and interpersonal affection

Lesioning

surgically graphing and dissecting the organic structures of the brain

EEG

records bioelectrical activity of the brain’s neural circuitry

CT (CAT) Scan

3D viewing; provide cross sectional images of the brain’s internal structures

PET

radioactive glucose is injected into carotid artery, providing energy needed for brain to perform a series of operation tasks

MRI

uses magnetic waves instead of radiation (like CT scan)

fMRI

video recordings of brain activity

Approximate mass of adult brain

3.2 lbs

Approximate % of body’s oxygen & blood supply

20%

Approximate energy expenditure

15-25 watts

Dura mater

thick, durable, outer membrane that covers brain & spinal cord

• physically protects central nervous system

Arachnoid mater

spongy middle layer with an appearance of a spider web used as a shock absorber and filled with cerebro spinal fluid

Pia mater

thin, permeable membrane closest to the brain’s tissue that provides pathways for cranial nerves & blood vessels to enter and exit the brain

Hindbrain

primitive structures shared by all vertebrate creatures that is responsible for basic autonomic functions and life support systems

Cerebellum (Hindbrain)

• mini brain

• body coordination

• balance / posture

• doesn’t make muscles move

• bi-hemispherical

Brain stem (Hindbrain)

• structural tissue that fuses the spinal cord to the brain

• responsible for life support

Reticular Formation (RF) (Hindbrain)

• In the brain stem

• complex system of nerve fibers composing the inner core of the brain stem

• sensory filter, screening 80% of incoming environmental signals

• regulates attention

• sensitive to threats

Pons Varolii (Hindbrain)

• In the brain stem

• regulates respiratory system

• temporary recycling bin for neural impulses filtered by the Reticular Formation

• plays an essential role in REM stages of sleep

Medulla Oblongata (Hindbrain)

• In the brain stem

• regulates circulatory system

• visceral reflex like swallowing, gagging, vomiting, blinking, etc.

Midbrain

system of structures bridging the primitive hindbrain and the advanced forebrain

• aids in perception

• aids in cognition

Basal Ganglia (midbrain)

• connects the cerebellum to the motor cortex

• timing of voluntary muscle movement

Accumbens Nucleus (midbrain)

• In the basal ganglia

• pleasure & reward system

• procedural learning, habitual behaviors, OCD

Thalamus (midbrain)

• receives filtered sensory messages from the Reticular Formation

• codes, sorts, and relays information to the cortex

Angular Gyrus (midbrain)

• in the thalamus

• multi sensory processor

• “parallel processing”

Hippocampus (midbrain)

• memory encoder

• selects the neural pathways through which memories are stored

Amygdala (midbrain)

• part of the limbic system

• responsible for generating primal, instinctive emotions

Hypothalamus (midbrain)

• “quality control center”

• regulates amygdala

• regulates pituitary gland

• regulates body temp

Suprachiasmatic Nucleus (midbrain)

• part of hypothalamus

• regulates biorhythms

Lateral Hypothalamus (midbrain)

• part of hypothalamus

• initiates hunger & thirst

Ventromedial Hypothalamus (midbrain)

• part of hypothalamus

• initiates satiety reflex

Limbic System

• network of hind/mid brain structures

• emotional instincts: anger, fear, panic

• survival instinctive functions

• Amygdala, hypothalamus, hippocampus, RF

Forebrain

• “Mammalian brain”

• responsible for complex, humanistic traits

• self aware, consciousness

• memory

• intelligence

• personality

Cerebrum (forebrain)

• largest part of the brain

• 80% of brain’s mass

• divided into 2 hemispheres

Left hemisphere

• controls the right side body functions

• analytical functions

• logical thought

• structured organization

• language

Right hemisphere

• controls the left side body functions

• creative functions

• emotional thought

• spatial relationships

• imaginative thinking

Corpus Callosum (forebrain)

• dense compacted band of axons & nerve fibers that bind the 2 cerebral hemispheres together

• neurological bridge that allows hemispheres to lateralize

Cerebral Cortex (forebrain)

• thin, wrinkly, external surface of the cerebrum

• contains 2/3 of brain’s neurons

• wrinkles = fissures = surface area expansion

• divided into 4 divisions

Frontal lobe

• largest surface area of the cortical lobes

• speech production

• mood related emotion

• personality

• voluntary muscle control

• advanced cognition

Motor Cortex (frontal lobe)

sends bioelectrical impulses to muscles to enable voluntary muscle movement

Ventromedial Prefrontal Cortex (frontal lobe)

responsible for judgement and decision making

Broca’s Area (frontal lobe)

association area responsible for vocal articulation needed for speech production

Temporal Lobe

• responsible for the perceptions of auditory sensations

• auditory cortex

• involved in long term storage of memory

Wernicke’s Area (temporal lobe)

area used for language comprehension

Transverse Temporal Gyrus (Heschl’s Gyrus) (temporal lobe)

responsible for vocal signature identification

A4 Medial Geniculate Nucleus (temporal lobe)

responsible for music processing

Lateral Superior Olive (temporal lobe)

responsible for source location for sound

Occipital lobe

• responsible for visual perceptions

• signals from left eye are processed within the right eye and vice versa

V1 Lateral Geniculate Nucleus (occipital lobe)

feature detector within visual cortex; perception & recognition of color

Fusiform gyrus (occipital lobe)

responsible for facial recognition

Inferior Gyrus (occipital lobe)

used for object recognition

Parietal Lobe

• responsible for perception of touch, taste, and smell

Somatosensory cortex (parietal lobe)

• processes body sensations

  • pressure

  • temperature

  • sense of pain

Insular cortex (parietal lobe)

• essential for eye-hand coordination

• allows for self consciousness

Reflex

a simple, autonomic/automatic response to a sensory stimulus

Threshold

the level of stimulation required to trigger a neural impulse

Refractory Period

a brief pause that occurs after a neuron has fired

All-or-none response

a neuron’s reaction of either firing or not

Agonist

molecule that increases neurotransmitter action

Antagonist

molecule that blocks or inhibits neurotransmitter action

Endocrine System

the body’s slow chemical communication system; a set of glands / fat tissue that secrete hormones into bloodstream

Hormones

chemical messengers that are made by the endocrine glands, travel through bloodstream, and affect other tissue

Phrenology

Study of bumps on the skull

Localization of a function

idea that various brain regions have particular functions

Levels of analysis

the differing levels from bio to psycho to socio-cultural for analyzing any phenomena