Chapter 7: Biological Bases: The Brain and Nervous System

Physiological psychology

is the study of behavior as influenced by biology.

Huntingtons chorea

is a genetic disorder that results in muscle impairment that does not typically occur until after age 40.

Roger Sperry

demonstrated that the two hemispheres of the brain can operate independently of each other.

Hippocampus

involved in processing and integrating memories.

terminal buttons

The axons end in ________, knobs on the branched end of the axon.

Stressful situations

cause the pituitary to release adrenocorticotropic hormone (ACTH), which stimulates the adrenal glands, resulting in fight- or- flight reactions.

EEG

(electroencephalogram) measures subtle changes in brain electrical activity through electrodes placed on the head.

Traits

are distinctive characteristics or behavior patterns that are determined by genetics.

formation

It also plays a role in learning, memory ________, and language processing.

Michael Gazzaniga

has not only done pioneering research in this area, focusing on split- brain patients, but also published works in cognitive neuroscience for the general reader.

axon

is a long, tubelike structure that responds to input from the dendrites and soma.

nodes of Ranvier

The myelin looks like beads on a string; the small gaps between the "beads "are known as the ________.

Reflexes

are quick and involuntary responses to environmental stimuli.

Thalamus

relays sensory information; receives and directs sensory information from visual and auditory systems.

forebrain

is responsible for higher- level thinking such as abstract thought and decision making.

REM

The pons is also implicated in ________ sleep.

genotype

is the genetic makeup of a cell or of an organism.

Genes

are the basic biological elements responsible for carrying information about traits between successive generations.

sensory information

It also plays an important role in processing ________ from the body and sending it back to other parts of the brain.

Excitatory neurotransmitters

serve to excite the cell or cause the neuron to fire.

MRI

uses extremely powerful electromagnets and radio waves to get 3- D structural information from the brain.

Functional MRI

(fMRI) and PET scans (positron emission tomography) do allow scientists to view the brain as it is working.

endocrine system

provides another way by which various parts of our bodies relay information to one another.

Inhibitory neurotransmitters

________ inhibit (or stop) cell firing.

terminal button

releases neurotransmitters, chemical messengers, across the synapse, where they bind with receptors on subsequent dendrites.

cortex

covers two symmetrical- looking sides of the brain known as the left and right cerebral hemispheres.

thyroid gland

located at the front of the neck, produces thyroxine, which is important for regulating cellular metabolism.

Leak channels

are channels that are open all the time and that simply allow ions to "leak "across the membrane according to their gradient.

sympathetic nervous system

is associated with processes that burn energy.

Peripheral nervous system

comprising all other nerves in the body.

parasympathetic nervous system

is the complementary system responsible for conserving energy.

Hypothalamus

controls the temperature and water balance of the body; controls hunger and sex drives; orchestrates the activation of the sympathetic nervous system and the endocrine system; and it can be divided into the lateral hypothalamus and ventromedial hypothalamus, the combination of which regulates eating behaviors and body weight.

forebrain

is the part of the brain located at the front of the head, consisting mainly of the cerebrum.

Nerves

are bundles of neurons, the basic unit of the nervous system.

**Imaging techniques**

allow researchers to map the structure and/or activity of the brain and correlate this data with behavior.

**Computerized axial tomography scans**

better known as **CAT scans,** generate cross-sectional images of the brain using a series of X-ray pictures taken from different angles.

afferent neurons

Nerves sending information to the brain are sensory

efferent neurons

those conveying information from the brain are motor

*somatic nervous system*

is responsible for voluntary movement of large skeletal muscles.

*autonomic nervous system*

controls the nonskeletal or smooth muscles, such as those of the heart and digestive tract.

**Medulla oblongata**

controls involuntary actions, such as breathing, digestion, heart rate, and swallowing (basic life functions)

**Pons**

Latin for “bridge,” the pons is a way station, passing neural information from one brain region to another.

**Cerebellum**

controls muscle tone and balance

**Reticular activating system (RAS**)

controls arousal (wakefulness and alertness).

**Paul Broca**

who observed that brain damage to the left hemisphere in stroke patients resulted in **expressive aphasia,** or loss of the ability to speak.

**Carl Wernicke**

discovered an area in the left temporal lobe that, when damaged in stroke patients, resulted in **receptive aphasia,** or the inability to comprehend speech.

**action potential**

also referred to as a **nerve impulse,** is a disturbance in this membrane potential.

**Excitatory**

neurotransmitters serve to excite the cell or cause the neuron to fire.

**Inhibitory**

neurotransmitters inhibit (or stop) cell firing.

**endocrine system**

provides another way by which various parts of our bodies relay information to one another.

hormones

a release substance from glands

**Down syndrome**

occurs when there are three copies of the 21st chromosome, which generally causes some degree of intellectual disability.

**Huntington’s chorea**

is a genetic disorder that results in muscle impairment that does not typically occur until after age 40.