Myers Exploring Psychology Chapter 2

MRI (magnetic resonance imaging)

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

PET (positron emission tomography) scan

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

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.

hormones

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

Broca's area

controls language expression-an aread of the frontal, 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

aphasia

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

cerebellum

the "little brain" attached to the rear of the brainstem; it helps coordinate voluntary movement and balance

sensory cortex

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

medulla

the base of the brainstem; controls heartbeat and breathing

endocrine

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

nervous system

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

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

dendrite

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

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations

parasympathetic nervous system

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

somatic nervous system

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

pituitary gland

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

axon

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

cerebral cortex

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

synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap or cleft.

corpus callosum

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

occipital lobes

the portion of the cerebral cortex lying at the back of the head; includes the visual areas, which receive visual information from the opposite visual field

frontal lobes

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

temporal lobes

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

plasticity

the property of being physically malleable, the brain's capacity for modification, as evident in brain reorganization following damage (especially in children) and in experiments on the effects of experience on brain development

central nervous system

The brain and spinal cord

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.

parietal lobes

The portion of the cerebral cortex lying at the top of the head and toward the rear; includes the sensory cortex

biological psychology

a branch of psychology concerned with the links between biology and behavior

split brain

a condition in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them.

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.

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

sensory neurons

neurons that carry incoming information from the sense receptors to the central nervous system.

threshold

the level of stimulation required to trigger a neural impulse

lesion

tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue

amygdala

two almond-shaped neural clusters that are components of the limbic system and are linked to emotion

motor cortex

An area at the rear of the frontal lobes that controls voluntary movements.

interneurons

Central nervous system neurons that internally communicate and intervene between the sensory inputs and motor outputs

neuron

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

reticular formation

a nerve network in the brainstem that plays an important role in controlling arousal

action potential

a neural impulse; a brief electrical charge that travels down an axon. the action potential is generated by the movement of positively charged atoms in and out of channels in the axon's membrane

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

neurotransmitters

chemical messengers that traverse the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

nerves

neural "cables" containing many axons. These bundled axons, which are part of the peripheral nervous system, connect the central nervous system with muscles, glands, and sense organs

motor neurons

neurons that carry outgoing information from the central nervous system to the muscles and glands

peripheral nervous system

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

endorphins

"morphine within"--natural, opiatelike neurotransmitters linked to pain control and to pleasure.

brainstem

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

hypothalamus

a neural structure lying below (hypo) 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.

adrenal glands

a pair of endocrine glands just above the kidneys. the adrenals secrete the hormones epinephrine (adrenaline) and norepinephrine (noradrenaline), which help to arouse the body in times of stress.

reflex

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