Unit 2

Reflex

unlearned, involuntary reaction to a stimulus; done through spinal cord

Lesion

removal or destruction of part of the brain (naturally or experimentally caused

EEG (Electroencephalogram)

uses electrodes to detect electrical activity of brain waves (used in sleep studies)

MEG Scan (magnetoencephalography)

a head coil measures magnetic fields generated by electrical signals in the brain

CT Scan (Computed Tomography)

x-ray of brain structure only; series of x-rays taken at different angles and combined by a computer to show a slice through the brain

PET Scan (Positron Emission Tomography)

uses radioactive glucose to locate activity in the brain; more color, more active brain (ONLY COLOR SCAN)

MRI (Magnetic Resonance Imaging)

Located brain material by using a magnetic field to send radio frequencies through the brain and measuring how these signals interact with brain cells. Computers transform these interactions into detailed images of the structure of the brain. (MOST DETAILED)

fMRI (functional magnetic resonance imaging)

A combination of a PET scan and MRI. Reveals blood flow (blood oxygen level) and therefore brain activity by comparing successive MRI scans (MOVING SCAN)

Medulla

blood pressure, heart rate, and breathing

Pons

facial expressions

Reticular Formation (aka reticular activating system)

body arousal/ability to focus (tic tock goes alarm clock-awakens you)

Thalamus

receives sensory signal and relays them to the rest of the body; contains sensory cortex - except SMELL

Cerebellum

balance, motor movement

Amygdala

emotions

Hypothalamus

hunger/thirst, sexual arousal, and body temperature

Hippocampus

formation of new memories

Cerebral Cortex

has the parietal lobe, occipital lobe, temporal lobe, and frontal lobe (prefrontal cortex)

Frontal Lobe (Prefrontal Cortex)

abstract thought, planning, emotion, judgment, decision making; located at the front of the face - forehead

Parietal Lobe

sensory cortex, sense of touch; top of head

Occipital Lobe

vision; back of the head

Temporal Lobe

auditory, sound; a little above the ear

Motor Cortex

sends signals to muscles and body, voluntary movement, located at the back of the frontal lobe

Sensory (aka somatosensory) Cortex

receives incoming touch sensations from the body, located at the front of the parietal lobe

Association Areas

any part of the cerebral cortex that does not control muscle movements or receive sensory information - these areas involve higher mental function (learning, remembering, speaking, thinking)

Aphasia

impaired use of language

Broca’s Area

speech production

Wernicke’s Area

language comprehension

Plasticity

the brain’s capacity for modification

Brain Lateralization (aka hemispheric specialization)

outdated theory suggesting that each hemisphere controls all functions but each hemisphere has distinct functions; left-language, right-spatial

Corpus Callosum

connects the 2 hemispheres and transmits messages between them; people who get epileptic seizures have this surgically removed therefore becoming split-brain patients

Gazzaniga/Sperry’s Split-Brain Studies

-corpus callosum is severed to reduce seizures in patients with uncontrollable epilepsy; can write a word they see in the right visual field but cannot say it because the left hemisphere controls language

-began splitting brains of cats and monkeys and found no serious effect

Behavioral Geneticist

the study of how genes and environment interact to shape behavior; use twin and adoption studies to learn the influences of genes and environment

Genes

building blocks for our physical development

Identical (monozygotic) Twins

twins, always the same gender, that developed by a single egg that split during mitosis and are fertilized by a single sperm; carry the same complement of genes

Fraternal (dizygotic) Twins

twins, of the same or different sex, that developed from two distinct eggs fertilized by two separate sperm

Heritability

the extent to which differences and/or abilities among people are attributable to genes

Epigenetics

the study of changes in gene expression that can be influenced by environmental factors and affect behavior and health

Sensory (Afferent) Neurons

senses to brain

Motor (Efferent) Neurons

brain to senses

Interneurons

Neurons of CNS; communicate between afferent and efferent neurons

Dendrite

receives information from other neurons

Axon

passes information to other neurons, muscles, and glands

Myelin Sheath

insulates the axon and conducts electrical impulses

(Causes multiple-sclerosis [was on AP test] )

Terminal Buttons (aka- terminal branches, axon terminals, end buttons, and synaptic knobs)

the branched end of an axon that contains neurotransmitters and sends nerve impulses [synaptic vesicles that hold neurotransmitters until released]

Action Potential

firing of an electrical charge in a neuron

Refractory Period

time it takes a neuron to recharge (can’t fire in this period)

Threshold

the minimum energy required for a neuron to fire

All or Nothing Response

neuron either fires or doesn’t

Synapse/ Synaptic Gap

the junction between the axon terminal and the dendrites of the receiving neuron which neurotransmitters go through to pass to the next neuron

Neurotransmitters

chemical messengers that allow neurons to communicate

Acetylcholine (ACh)

-neurons in the hippocampus for most memories

-enables muscle action, learning, and memory

Dopamine

influences movement, learning, attention, and emotion

Serotonin

affects mood, hunger, sleep, and arousal

Norepinephrine

helps control alertness and arousal

GABA (gamma-aminobutyric acid)

a major inhibitory neurotransmitter

Endorphins

natural, opiate-like neurotransmitters linked to pain control and to pleasure

Agonist

mimic the action of neurotransmitters by blocking reuptake; speed up cell firing

Antagonist

block neurotransmitters by blocking receptor sites; slow down cell firing

Central Nervous System

• Brain and spinal cord

• involved in mental activities and in coordinating and integrating incoming sensory messages and outgoing motor messages.

Peripheral Nervous System

• All other nerves in the body that are not part of the brain and spinal cord.

• To link the CNS to the rest of the body.

Somatic Nervous System

• Apart of the PNS

• controls voluntary movement

Autonomic Nervous System

• controls involuntary/automatic functions

• Apart of the PNS

Sympathetic Nervous System

preps body to respond to stress

Parasympathetic Nervous System

slows our body down after stress

Neural Network

interconnectedness of bodies neurons