intro to psychology - chapter 2

sensory neurons

a neuron that responds to signals from sensory organs (eyes, ears, nose, tongue, skin) and transmits those signals to the brain and spinal cord.

motor neurons

a neurons that sends signals to muscles in order to control movement (and also to bodily organs, such as glands).

interneurons

a neuron that is connected to other neurons, not to sense organs or muscles. (this is what most neurons in the brain are)

neurons

these work together to accomplish tasks such as produce a sentence or catch a ball

brain circuits

a set of neurons that works together to receive input, operates on it in some way, and produces specific output.

dendrites

part of a neruon that receives signals from axons of other neutrons

cell body

the central part of the neuron and contains a nucleus that regulates the neuron’s functions

terminal buttons

part of a neuron that releases chemicals into the spaces between neurons when activated by their neuron

cell membrane

part of neuron that protects the cell body

axon

part of a neuron that is a long, cable-like structure that conveys signals to other neurons, muscles, or bodily organs

terminals

axons divide into branches and the ends are called _______

chemicals

what are the inputs and outputs that neurons deal with called?

resting potential

the negative charge within neuron when it is at rest

ions

atoms that are positively or negatively charged

action potential

the shifting change in charge that moves down the axon

all or none law

states that if the neuron is sufficiently stimulated, it fires, sending the action potential all the way down the axon and releasing chemicals from the terminal buttons; either the action potential occurs or it doesn’t.

myelin

most axons are covered in this (a fatty substance that helps impulses efficiently travel down the axon

synapse

the place where an axon of one neuron sends signals to the membrane (on a dendrite or cell body) of another neuron; the synapse includes the sending portions of an axon, the receiving portions of the receiving neuron, and the space between them.

synaptic cleft

the gap in the synapse between the axon of one neuron and the membrane of another, across which communication occurs..

neurotransmitter substances

aka neurotransmitters - a chemical that carries a signal from the terminal button to the dendrite or cell body of another

acetylcholine

causes muscles to contract, memory; arousal

dopamine

motivation, reward, movement, thought, learning

noradrenaline (norepinephrine)

dreaming, attention

glumate

primary excitatory neurotransmitter, involved in learning and memory

endorphins

involved in modulating pain perception

seretonin

primary inhibition neurotransmitter regulating mood and sleep

GABA (gamma-amninobutyric acid)

inhibits sending neuron

endogenous cannabinoids

neurotransmitter substances released by the receiving neuron that then influence the activity of the sending neuron (memory, attention, emotion, movement, control, appetite, etc.)

receptors

a site on a dendrite or cell body where a neurotrasmitter molecule attaches itself; like a lock that is opened by one key, a receptor receives only one type of neurotransmitter

reuptake

the process by which surplus neurotransmitter in the synaptic cleft is reabsorbed back into the sending neuron so that the neuron can effectively fire again

agonists

a chemical that mimics the effects of a neurotransmitter by activating a type of receptor

SSRIs - selective seretonin reuptake inhibitors

a chemical that blocks the reuptake of the neurotransmitter seretonin

SNRIs - seretonin-norepinephrine reuptake inhibitors

a chemical that blocks the reuptake of the neurotransmitters seretonin and norepinephrine

antagonist

a chemical that blocks the effects of a neurotransmitter

cause of diseases like parkinsons

death of some of the cells that produce dopamine

glial cells

a type of cell that helps neurons to form both synapses and connections when the brain is developing, influences the communication among neurons, and generally helps in the “care and feeding” of neurons

neurons have synapses with glial cells, and they stimulate glial cells to release specific chemicals

how neurons and glial cells influence eachother

the nervous system’s 2 major parts

the nevous system and the peripheral nervous system

peripheral nervous system

crucial for getting information into and out of the brain, and then provides a very general overview of the central nervous system, which consists of the brain and the spinal cord

the automatic nervous system (ANS)

controls the smooth muscles in the body, some glandular functions, and many of the body’s self-regulating activities, such as digestion and circulation

peripheral nervous system (PNS)

the autonomic nervous system and the somatic nervous system

sympathetic nervous system

part of the autonomic nervous system that readies an animal to fight or to flee by speeding up the heart, increasing the breathing rate to deliver more oxygen, dialating the pupils, producing sweat, decreasing salvation, inhibiting activity in the stomach, and relaxing the bladder

parasympathetic nervous system

part of the autonomic nervous system that is “next to” the sympathetic nervous system and that tends to counteract its effects.

somatic nervous system (SNS)

part of the peripheral nervous system that consists of neurons in the sensory organs (such as eyes and ears) that convey information to the brain as well as neurons that actully trigger muscles and glands

somatic motor system

consists of nerves that are attached to muscles that can be used voluntarily (striated muscles)

spinal cord

the largest conduit for information going to and from the brain is in the ______ _______ (the flexible rope of neurons and their connections that runs inside the backbone aka spinal column)

central nervous system (SNS)

the spinal cord and the brain are connected and called the _________ _________________

reflex

an automatic behavioral response to an event, an action that does not require thought, most require hundreds of neurons

meninges

3 protective layered membranes that cover the brain

cerebral hemisphere

a left or right half of the brain, shaped roughly like half a sphere

corpus callosum

the large bundle of axons that connects the two halves of the brain

cerebral cortex

the convoluted pinkish-gray outer layer of the brain, where most mental processes arise

sulci

creases in the cerebral cortex

gyri

bugles between sulci in the cerebral cortex

subcortical (under the cortex) structures

parts of the brain located under the cerebral cortex

brain system

a set of brain circuits that work together to accomplish a particular task

occipital lobes

the brain lobes located at the back of the head, concerned entirely with different aspects of vision

temporal lobes

the brain lobes under the temples, in front of the ears; among their many functions are processing sound, entering new information into memory, storing visual memories, and comprehending language

parietal lobes

the brain lobes at the top, rear of the brain; they are involved in attention, arithmetic, touch, and registering spatial location

somatosensory strip

the gyrus immediately behind the central sulcus; it registers sensations on the body and is organized by body part

frontal lobes

the brain lobes located behind the forehead, critically involved in planning, memory search, motor control, speech control, reasoning, and emotions

motor strip

aka primary motor cortex; the gyrus immediately in front of the central sulcus; it controls fine movements and is organized by body part

split-brain patient

a person whose corpus callosum has been servered for medical reasons, so that neural signals no longer pass from one cerebral hemisphere to another

left brain vs right brain

left brain is verbal and analytical, and the right brain is perceptual and intuituve

brain to function communcations

moving left hand is controlled by right hemisphere

thalamus

a subcortial structure that receives signals from sensory and motor systems and plays a crucial role in attention, sleep, and other functions critical to daily life; often thought of as a switching center

hypothalamus

a brain structure that sits under the thalamus and plays a central role in controlling eating and drinking and in regulating the body’s temperature, blood pressure, heart rate, sexual behavior, and hormones.

hippocampus

a subcortial structure that plays a key role in allowing new information to be stored in the brain’s memory banks

amygdala

a subcortial structure that plays a special role in fear and is involved in other types of strong emotions, such as anger

limbic system

a set of brain areas, including the hippocampus, amygdala, hypothalamus, and other areas, that has long been thought of as being involved in key aspects of emotion and motivation, namely, those underlying fighting, fleeing, feeding, and sex. (it also stores family)

basal ganglia

subcortical structures that play a role in planning, learning new habits, and producing movement

brainstem

the set of structures at the base of the brain—including the midbrain, medulla, and pons—that feed into and receive information from the spinal cord.

medulla

the lowest part of the lower brainstem, which plays a central role in the automatic control of breathing, swallowing, and blood circulation.

reticular formation

a collection of small structures in the brainstem, organized into two main parts: the reticular activating system and another part that is important in producing autonomic nervous system reactions.

pons

a bridge between the medulla and midbrain, which also connects the upper parts of the brain to the cerebellum.

cerebellum

a lrge structure at the base of the brain that is concerned in part with physical coordination, estimating time, and paying attention

hindbrain

according to a historical way of organizing brain structures, a unit of the brain that includes the medulla, pons, cerebellum, and parts of the reticular formation.

midbrain

according to a historical way of organizing brain structures, a unit of the brain that includes parts of the reticular formation as well as the brainstem structures that lie between forebrain and hindbrain.

hormones

a chemical that is produced by a gland and can act as a neurotransmitter substance.

the neuroendocrine system

makes hormones that affect many functions and provides the CNS with information

testosterone

hormone that causes males to develop facial hair and other external sexual characteristics, and to build up muscle volume.

estrogen

hormone that causes girls to develop breasts and is involved in the menstrual cycle.

cortisol

a hormone produced by the outer layer of the adrenal glands that helps the body cope with the extra energy demands of stress.

pituitary gland

 “master gland” that regulates other glands but is itself controlled by the brain, primarily via connections from the hypothalamus.

hypothalamic-pituitary-adrenal (HPA) axis

system of the hypothalamus, pituitary gland, and adrenal glands that is activated by stress, injury, and infection and that works to fight off infection.

lesion

a region of impaired brain tissue

stroke

cause of brain damage that occurs when blood (with its life-giving nutrients and oxygen) fails to reach part of the brain, causing neurons in that area die.

electroencephalograph

a machine that records electrical activity in the brain

electroencephalogram (EEG)

a tracing of the changes over time in electrical activity of the brain

magnetoencephalography (MEG)

technique for assessing brain activity that relies on recording magnetic waves produced by neural activity.

single-cell recording

technique in which tiny probes called micro- electrodes are placed in the brain and used to record neural firing rates.

neuroimaging

brain-scanning techniques that produce a picture of the structure or functioning of regions of the brain.

computer assisted tomography (CT, formerly CAT)

neuroimaging technique that produces a three-dimensional image of brain structures using X-rays.

magnetic resonance imaging (MRI)

technique that uses magnetic properties of atoms to take sharp pictures of the three-dimensional structure of the brain.

positron emission tomography (PET)

neuroimaging technique that uses small amounts of a radioactive substance to track blood flow or energy consumption in the brain.

functional magnetic resonance imaging (fMRI)

type of magnetic resonance imaging that detects the amount of oxygen being brought to particular places in the brain, which indicates how active those neurons are.

transcranial magnetic stimulation (TMS)

technique in which the brain is stimulated from outside by putting a coil on a person’s head and delivering a magnetic pulse (or series of magnetic pulses); the magnetic fields are so strong that they make neurons under the coil fire.

mendelian inheritance

transmission of characteristics by individual elements of inheritance (now known to be genes), each acting separately.

gene

a stretch of the DNA molecule that produces a specific protein.

genotype

the genetic code within an organism.