Unit 1a

biological psychology

a branch of psychology that studies the links between biological (including neuroscience and behavior genetics) and psychological processes

Neuron

a nerve cell; the basic building block of the nervous system

sensory/afferent neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

motor/efferent neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

Interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

Dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

Axon

the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands

myelin sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

action potential

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

threshold

the level of stimulation required to trigger a neural impulse

Synapse/synaptic gap

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons.

Reuptake

a neurotransmitter's reabsorption by the sending neuron

nervous system

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

central nervous system

brain and spinal cord

peripheral nervous system

the sensory and motor neurons that connect the central nervous system to the rest of the body

Nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs

somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles

consciously sense and do

autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations (fight or flight)

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy

reflex

a simple, automatic response to a sensory stimulus, such as the knee-jerk response

endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

Hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

adrenal glands

a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

pituitary gland

The endocrine system's most influential gland. Under the influence of the hypothalamus, it regulates growth and controls other endocrine glands.

lesion

tissue destruction. Naturally or experimentally caused destruction of brain tissue

Electroencephalogram (EEG)

An amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp.

CT scan

a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body

PET scan

a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

MRI

a technique that uses magnetic fields and radio waves to produce computer-generated images that distinguish among different types of soft tissue; allows us to see structures within the brain

fMRI

A technique for revealing blood flow and brain activity by comparing successive MRI scans.

Brain stem

the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; responsible for automatic survival functions

Medulla

the base of the brainstem; controls heartbeat and breathing

reticular formation

a nerve network in the brainstem that plays an important role in controlling arousal and general ability to focus

region present inside the medulla, containing a network of nerve fibers. It is involved in increasing alertness, attention, and consciousness (sleep-wake cycles)

Thalamus

the brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

relay station

Cerebellum

the "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance

limbic system

A doughnut-shaped system of neural structures at the border of the brainstem and cerebral hemispheres; associated with emotions such as fear and aggression and drives such as those for food and sex. Includes the hippocampus, amygdala, and hypothalamus.

Amygdala

two lima bean-sized neural clusters in the limbic system; linked to emotion (fear, emotional memory and aggression)

part of the limbic system

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.

cerebral cortex

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center.

glial cells

cells in the nervous system that support, nourish, and protect neurons

frontal lobes

the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments

parietal lobes

portion of the cerebral cortex lying at the top of the head and toward the rear

receives sensory input for touch and body position (manages 5 senses)

occipital lobes

portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields

temporal lobes

portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear

motor cortex

an area at the rear of the frontal lobes that controls voluntary movements

sensory cortex

area at the front of the parietal lobes that registers and processes body touch and movement sensations

association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

aphasia

impairment of language, usually caused by left hemisphere damage either to Broca's area (impairing speaking) or to Wernicke's area (impairing understanding).

Broca's area

Controls language expression - an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved in speech.

Wernicke's area

controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe

Plasticity

the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

neurogenesis

the formation of new neurons

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

split brain

a condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them

consciousness

our awareness of ourselves and our environment

cognitive neuroscience

`the interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language)

dual processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks

behavior genetics

the study of the relative power and limits of genetic and environmental influences on behavior

environment

every nongenetic influence, from prenatal nutrition to the people and things around us

Chromosomes

threadlike structures made of DNA molecules that contain the genes

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

Genes

`the biochemical units of heredity that make up the chromosomes; a segment of DNA capable of synthesizing a protein

Genome

the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes

identical twins

twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms

fraternal twins

twins who develop from separate fertilized eggs. They are genetically no closer than brothers and sisters, but they share a fetal environment.

Heritability

The proportion of variation among individuals that we can attribute to genes. May vary depending on the range of populations and environments studied.

interaction

the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)

molecular genetics

the subfield of biology that studies the molecular structure and function of genes

evolutionary psychology

the study of the evolution of behavior and the mind, using principles of natural selection

natural selection

the principle that, among the range of inherited trait variations, those contributing to reproduction and survival will most likely be passed on to succeeding generations

Mutation

a random error in gene replication that leads to a change

Serotonin

A neurotransmitter that affects hunger, sleep, arousal, and mood.

Lack of this leads to depression, anxiety, insomnia, OCD

Norepinephrine

arousal in the fight/flight response when in danger. Also stress, arousal, and eating

undersupply can depress mood, anxiety, stress, nervous tension

Acetylcholine

Enables involuntary muscle action (central nervous system - cardiac contractions, blood pressure), learning, and memory

Linked with Alzheimer's disease and paralysis

Glutamate

Enhances transmission of information to the brain

Too much can cause seizures or migraines

GABA

a major inhibitory neurotransmitter

Helps balance and offset other excitatory messages (calming)

Regulates sleep-wake cycles

Lacking can cause anxiety, seizures, tremors, or insomnia

Too much can cause sleeping disorders or some eating disorders

Endorphins

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

Involved in pain control

Released during aerobic exercise & linked to positive emotions (i.e. "runners high")

Not enough can cause the body to experience pain

Too much, body may not give adequate warning about pain

You can have an artificial high

Many of our most addictive drugs deal with these

Dopamine

Involved in voluntary muscle movements, attention, learning, memory, emotional arousal, & rewarding sensations

Lack of it has been linked to Parkinson's disease

Too much has been linked to addiction, schizophrenia or schizophrenic-like symptoms such as hallucinations and perceptual disorders

substance P

Pain perception and the immune system

primarily associated with the transmission of pain signals, making it essential for the body's pain perception mechanism. This neuropeptide can be released in response to various stimuli, including physical injury, stress, and inflammatory processes.

Too much can cause chronic pain

CT vs PET

CT: scans pass x-rays through the body to create images, in minutes

PET: uses radioactive material which emits energy to produce images, more time consuming

refractory period

state of recovery that occurs after a neuron has fired an action potential

neurons firing is all or nothing