Psychology - Chapter 2

Biological psychology

a branch of psychology concerned with the links between biology and behavior (better understanding of sleep and dreams, depression and schizophrenia, hunger and sex, stress and diseases)


body's information system is built from billions of interconnected cells; a nerve cell; the basic building block of the nervous system


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


the extension of a neuron, ending in ranching terminal fibers, through which messages pass to other neurons or to muscles/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 travenls down an axon; the action potential is generated by the movement of positively charged atoms in and out of channels in the axon's membrance

Resting potential

the state of being positive outside/negative inside


the level of stimulation required to trigger a neural impulse


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


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 neuron will generate a ne


the process in which excess neurotransmitters are reabsorbed by the sending neuron


a neurotransmitter that enables learning and memory and also triggers muscle contraction


influences movement, learning, attention, and emotion


affects mood, hunger, sleep, and arousal


helps control alertness and arousal


(gamma-aminibutyric acid) a major inhibitory neurostramitter


a major excitatory neurotransmitter; involved in memory


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

Blood-brain barrier

enables the brain to fence out unwanted chemicals circulating in the blood

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

the brain and spinal cord

Peripheral nervous system

the sensory and motor neurons that connect the CNS to the rest of the body


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

Sensory neurons

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

Motor neurons

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


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

Somatic nervous system

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

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); it's sympathetic division arouses; it's parasympathetic division calms

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


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

Neural networks

interconnected neural cells; with experience, networks can learn as feedback strengthens or inhibits connections that produce certain results; computer simulations of neural networks show analogous learning

Endocrine system

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


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

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

Pituitary gland

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


tissue destruction; a brain lesion is a naturally or experimentally caused destruction of brain tissue


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

PET scan

(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


(magnetic resonance imaging) - 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


(functional magnetic resonance imaging) - a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans; MRI scans show brain anatomy; fMRI scans show brain function


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

medulla -

the base of the brainstem; controls heartbeat and breathing


helps coordinate movements

reticular formation

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


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


the "little brain" attached to the rear of the brainstem; its 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, amygdale


two lima bean sized neural clusters that are components of the limbic system and are linked to emotion


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

cerebral cortex

the intricate fabric of interconnected neural cells that covers 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

the portion of the cerebral cortext lying at the top of the head and toward the rear; receives sensory input for touch and body position

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

Temporal lobes

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

Motor cortex

an area of the rear of the frontal loves that controls voluntary movements

Sensory cortex

the area at the front of the parietal loves 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


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 love, usually in the left hemisphere, that directs the muscle movements involved in speech

Wernicke's area

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


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

Visual cortex

receives written words as visual stimulation

Angular gyrus

transforms visual representations into an auditory code

Left hemisphere

impair reading, writing, speaking, arithmetic reasoning, and understanding

Corpus callosum

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

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