Chapter 2: Neuroscience, Genetics, and Behavior

Question 1

Biological Psychology

Answer 1

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

Question 2

Neuron

Answer 2

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

Question 3

Dendrite

Answer 3

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

Question 4

Axon

Answer 4

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

Question 5

Myelin

Answer 5

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.

Question 6

Action Potential

Answer 6

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.

Question 7

Threshold

Answer 7

the level of stimulation required to trigger a neural impulse.

Question 8

Synapse

Answer 8

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.

Question 9

Neurotransmitters

Answer 9

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.

Question 10

Acetylcholine (ACh)

Answer 10

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

Question 11

Endorphins

Answer 11

our body’s “natural morphine”; neurotransmitter linked to pain control and to pleasure.

Question 12

Nervous System

Answer 12

the body’s speedy, electro-chemical communication system, consisting of all the nerve cells of the peripheral and central nervous systems.

Question 13

Central Nervous System (CNS)

Answer 13

the body system composed of the brain and the spinal cord.

Question 14

Peripheral Nervous System (PNS)

Answer 14

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

Question 15

Nerves

Answer 15

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.

Question 16

Sensory (Afferent) Neurons

Answer 16

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

Question 17

Motor (Efferent) Neurons

Answer 17

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

Question 18

Interneurons

Answer 18

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

Question 19

Somatic Nervous System

Answer 19

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

Question 20

Autonomic Nervous System

Answer 20

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.

Question 21

Sympathetic Nervous System

Answer 21

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

Question 22

Parasympathetic Nervous System

Answer 22

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

Question 23

Reflex

Answer 23

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

Question 24

Neural Networks

Answer 24

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.

Question 25

Endocrine System

Answer 25

the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream.

Question 26

Hormones

Answer 26

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

Question 27

Adrenal Glands

Answer 27

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.

Question 28

Pituitary Glands

Answer 28

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

Question 29

Lesion

Answer 29

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

Question 30

Electroencephalogram (EEG)

Answer 30

an amplified recording of the waves of electrical activity that sweep across the brains surface. Waves are measured by electrodes placed on the scalp

Question 31

Positron Emission Tomography (PET)

Answer 31

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

Question 32

Magnetic Resonance Imaging (MRI)

Answer 32

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.

Question 33

Functional Magnetic Resonance Imaging (fMRI)

Answer 33

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.

Question 34

Braistem

Answer 34

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.

Question 35

Medulla

Answer 35

the base of the brainstem; controls heartbeat and breathing.

Question 36

Reticular Formation

Answer 36

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

Question 37

Thalamus

Answer 37

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.

Question 38

Cerebellum

Answer 38

the “little brain” attached to the rear of the brainstem; its functions include processing sensory input and coordinating movement output and balance.

Question 39

Limbic System

Answer 39

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.

Question 40

Hypothalamus

Answer 40

a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion.

Question 41

Amygdala

Answer 41

two lima bean-sized neural clusters that are components of the limbic system and are linked to emotion, specifically fear and anger.

Question 42

Cerebral Cortex

Answer 42

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

Question 43

Glial Cells

Answer 43

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

Question 44

Frontal Lobes

Answer 44

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

Question 45

Parietal Lobes

Answer 45

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

Question 46

Occipital Lobe

Answer 46

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.

Question 47

Temporal Lobes

Answer 47

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.

Question 48

Motor Cortex

Answer 48

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

Question 49

Sensory Cortex

Answer 49

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

Question 50

Corpus Callosum

Answer 50

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

Question 51

Split Brain

Answer 51

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.

Question 52

(Brain/Neural) Plasticity

Answer 52

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.

Question 53

Association Areas (Grey Matter)

Answer 53

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.

Question 54

Aphasia

Answer 54

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

Question 55

Broca’s Area

Answer 55

controls language expression- an area of the left frontal lobe that directs the muscle movements involved in speech.

Question 56

Wernicke’s Area

Answer 56

controls language reception- an area of the left temporal lobe involved in language comprehension and expression.