Ch 2 - The Biology of Behavior

echolocation

Determining the location of something by measuring the time it takes for an echo to return from it

agonists

Drugs that increase the action of a neurotransmitter.

neurogenesis

Formation of new neurons.

endocrine system

Glands secrete hormones that regulate processes such as growth, reproduction, and nutrient use (metabolism) by body cells.

gonads

Hormone-producing sex glands. Testes in the male; ovaries in the female.

aphasia

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

alcohol

It slows neural processing and can disrupt memory formation if consumed in large quantities. It can also increase the chances of disinhibiting its users, or slowing the brain activity involved in judgment and decision making.

engram

Lashley's biochemical term for memory trace.

spinal cord

Main link between the brain and sensory and motor systems.

neurotransmitters

Naturally produced chemicals that are released by nerve cells and that initiate or facilitate transmission of messages among nerve cells (e.g., serotonin, dopamine, norepinephrine, and acetylcholine

Sympathetic Nervous System

Part of the autonomic nervous system that instigates the physiological responses that accompany emotional behavior.

Parasympathetic Nervous System

Part of the autonomic nervous system, slows your heart rate, steadies your trembling, increases your control over bowel and bladder functioning, and in other ways opposes some of the functions of the sympathetic nervous system.

Somatic Nervous System

Part of the peripheral nervous system concerned with bodily sensations and muscular movement (controls voluntary actions).

nicotine

People with a crippling addiction to it generally resort to smoking as their primary route of administration. When a person smokes a cigarette, they feel the effects about as quickly and powerfully as heroin or cocaine.

all or none principle

Refers to the fact that the action potential in the axon occurs either full blown or not at all.

sleep spindles

Short bursts of brain waves detected in stage 2 sleep

theta waves

Slow brain waves (4 to 7 per second) characteristic of the early stages of sleep.

alpha waves

Slower, deeper brain waves characteristic of deep relaxation, having a frequency of 8 to 13 cycles per second.

rapid eye movement sleep

Sometimes referred to as the Stage 5 of sleep, the stage during which most of our dreaming occurs.

receptors

Specialized cells or groups of cells that respond to sensory stimulation.

opiates

Such as morphine and heroin; they depress neural activity, temporarily lessening pain and anxiety.

hynopsis

Technique in which a person employs methods to increase another's susceptibility to suggestion.

Autonomic Nervous System

That part of the peripheral nervous system that is not ordinarily under conscious control (involuntary actions). Includes the sympathetic and parasympathetic system

Central Nervous System

The human nervous system, which includes the brain and the spinal cord.

forebrain

The hypothalamus, concerned with temperature regulation and circadian rhythms; the thalamus, a relay center; the limbic system, implicated in emotions; and the cerebrum, divided into the four cerebral lobes, which include the visual and auditory cortices and the association areas of the brain.

pituitary gland

The master gland involved in controlling functioning of other endocrine glands.

hindbrain

The medulla, pons, and cerebellum, involved in balance and locomotion, respiration, sleep, and arousal.

threshold

The minimum level of stimulation needed for a neuron to fire an action potential.

Peripheral Nervous System

The neural networks that fan out from the central nervous system to various parts of the body.

reuptake

The process by which a nerve cell recaptures some of the neurotransmitters it has released.

midbrain

The reticular formation, involved in arousal and motivation.

evolution

The sequence of events involved in the evolutionary development of a species or taxonomic group of organisms.

non rapid eye movement sleep

The stage of sleep during which the eyes move very little and the body gradually reaches its state of deepest relaxation.

connectors

They serve as links between receptor and effector systems

beta waves

Typical shallow and rapid brain waves of person who is awake, having a frequency of 13 to 30 cycles per minute.

eye-fixation method

Uses an object to focus the subject's attention while the hypnotist speaks.

delta waves

Very slow brain waves (frequency of up to 4 per second) characteristic of deep sleep.

circadian rhythm

A biological/behavioral cycle that is approximately 1 day long. It describes our sleep/wake and temperature cycles.

refractory period

A brief period after firing during which a neuron is "discharged" and is incapable of firing again.

Parkinson's disease

A central nervous system disease characterized by tremors, slow movement, and other symptoms; associated with low dopamine levels in the brain.

suggestibility

A characteristic of a hypnotic state wherein subjects become exceedingly ready to believe whatever is suggested by the hypnotist and willing to perform whatever activities are asked of them.

psychoactive drug

A chemical substance that has the ability to alter perception, mood, behavior, and/or physiological function.

brain

A complex clustering of nerve cells that is centrally involved in coordinating activities and events in various parts of an organism. Reputedly the most complex structure in the universe.

nervous system

A conglomeration of billions of cells specifically designed to provide a communication network within the human body.

attention deficit hyperactivity disorder

A disorder marked by excessive general activity for a child's age, attention problems, high impulsivity, and low frustration tolerance. Also termed hyperactivity.

Sapir-Whorf hypothesis

A hypothesis concerning the role of language in shaping our interpretation of reality. It holds that language is culturally determined.

holistic education

A label for educational approaches that attempt to remedy what is seen as the failure of traditional education to educate the whole brain—especially the right hemisphere, which is speculatively linked with music, art, and emotion.

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.

axon

A long, thin fiber that transmits impulses away from the neuron cell body to other neurons, or to muscles or glands.

melatonin

A natural hormone closely tied to sleep/wake cycles. Also called the sleep hormone.

dopamine

A neurotransmitter associated with movement, attention and learning and the brain's pleasure and reward system.

norepinephrine

A neurotransmitter linked with arousal, memory, and learning. Also called noradrenaline

acetylcholine

A neurotransmitter present in the peripheral as well as central nervous system, involved in voluntary activity as well as physiological functions (such muscle contraction).

serotonin

A neurotransmitter, the bulk of which is found in the gut, where it regulates intestinal activity. Too low levels of serotonin may be associated with depression.

adrenal glands

A pair of endocrine glands that sit just above the kidneys and secrete hormones that help arouse the body in times of stress.

synapse

A physical gap between two neurons that functions as the site of information transfer from one neuron to another.

multiple sclerosis

A progressive disease of the nervous system that involves a degeneration of the myelin that surrounds nerve fibers in the brain and spinal cord.

action potential

A pulse- like electrical discharge along a neuron.

dream

A sequence of images, emotions, and thoughts passing through a sleeping person's mind.

neurons

A single nerve cell, the smallest unit of the nervous system and its basic structural unit. The function of the neuron is to transmit impulses, which are basically electrical but are made possible through chemical changes.

effectors

A specialized cell or organ that carries out a response to a nerve impulse.

dependent

A state of being characterized by the compulsive desire to have a substance, such as a drug, in order to feel "normal" and postpone the effects of withdrawal.

mind

A term referring primarily to human consciousness.

depressant

A type of drug that slows down physiological functions. (Alcohol is a commonly abused depressant and it slows down respiration.)

stimulant

A type of drug that speeds up physiological functions. (Cocaine is an abused stimulant and it speeds up the heart rate.)

adrenaline

Also called epinephrine. A substance produced by the adrenal glands, released in response to stress.

sleep

Altered state of consciousness; melatonin might be a significant neurochemical in this process.

paradoxical sleep

Another label for REM sleep, so called because during this stage of sleep physiological functions such as heart and respiration rate are very similar to those of a waking state.

cocaine

Another popular stimulant that influences dopamine levels in the brain and is usually snorted in its powdered form, or smoked in its freebase form. Produces reinforcing and addictive effects in its users by blocking the reuptake mechanisms of dopamine, serotonin, and norepinephrine, resulting in more of these neurotransmitters left in the synapse, and the "feel good" feeling that follows.

consciousness

Awareness of one's personal identity. Self-awareness. Awareness of mental processes like thinking, imagining, and feeling.

dendrites

Branchlike parts of a neuron that are specialized to receive information.

nerves

Bundles of fibers consisting of neurons, whose functions is the transmission of neural impulses.

hormones

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another.

antagonists

Chemical substances that block or reduce a cell's response to the action of other chemicals or neurotransmitters.