Chapter 4: The Brain and Behavior

Thalamus

Has sometimes been likened to a switchboard that organizes inputs from sensory organs and routes them to the appropriate areas of the brain.

Electroencephalograph

Measures the activity of large groups of neurons through a series of large electrodes placed on the scalp.

Hypothalamus

Plays a major role in many aspects of motivation and emotion, including sexual behavior, temperature regulation, sleeping, eating, drinking, and aggression.

Hindbrain

Is the lowest and most primitive level of the brain.

Neurotransmitters

Chemical substances that carry messages across the synaptic space to other neurons, muscles, or glands.

Inhibitory or excitatory

Involved in mood, sleep, eating, and arousal, and may be an important transmitter underlying pleasure and pain.

Cerebellum

Concerned primarily with muscular movement coordination, but it also plays a role in learning and memory.

Homeostasis

A delicately balanced or constant internal state.

Mindbrain

Contains clusters of sensory and motor neurons.

Functional MRI (fMRI)

Which can produce pictures of blood flow in the brain taken within seconds of one another.

Dendrites

Specialized receiving units like antennae that collect messages from neighboring neurons and send them on to the cell body.

Axon

Which conducts electrical impulses away from the cell body to other neurons, muscles, or glands.

Amygdala

Organizes motivational and emotional response patterns, particularly those linked to aggression and fear.

Reticular Formation

Acts as a kind of sentry, both alerting higher centers of the brain that messages are coming and then either blocking those messages or allowing them to go forward.

Aphasia

The partial or total loss of the ability to communicate.

Positron Emission tomography (PET) Scans

Measure brain activity, including metabolism, blood flow, and neurotransmitter activity.

Psychoactive Drugs

Chemicals that produce alterations in consciousness, emotion, and behavior.

Excitatory

Involved in voluntary movement, emotional arousal, learning, memory, and experiencing pleasure or pain.

Receptor Sites

Large protein molecules embedded in the receiving neurons cell membrane.

Medulla

Plays an important role in vital bodily functions such as heart rate and respiration.

Computerized Axial Tomography (CT or CAT) scans

Use X- ray technology to study brain structures.

neural circuits

Excitatory and inhibitory functions at various sites; involved in ________ controlling learning, memory, wakefulness, and eating.

Lateralization

The relatively greater localization of a function in one hemisphere or the other.

Myelin Sheath

A whitish, fatty insulation layer derived from glial cells during development.

Interneurons

Perform connective or associative functions within the nervous system.

Corpus Callosum

A neural bridge consisting of white myelinated fi bers that acts as a major communication link between the two hemispheres and allows them to function as a single unit.

Reuptake

In which the transmitter molecules are taken back into the presynaptic axon terminals.

Cerebrum

Consists of two large hemispheres, a left side and a right side.

Synaptic Vesicles

Chambers within the axon terminals.

Neurogenesis

The production of new neurons in the nervous system.

Endocrine System

Consists of numerous hormone- secreting glands distributes throughout the body.

Forebrain

The brains most advanced portion from an evolutionary standpoint.

Parasympathetic Nervous System(PNS)

Is far more specific in its opposing actions, affecting one or a few organs at a time.

Central Nervous System(CNS)

Contains the brain and the spinal cord, which connects most parts of the peripheral nervous system with the brain.

Pons

Lies just above the medulla and carries nerve impulses between higher and lower levels of the nervous system.

Broncas Area

In the frontal lobe, is mainly involved in the production of speech through its connections with the motor cortex region that controls the muscles used in speech.

Neural Plasticity

Refers to the ability of neurons to change in structure and function.

Sensory Neurons

Carry input messages from the sense organs to the spinal cord and brain.

Synaptic Space

A tiny gap between the axon terminal and the next neuron.

Wenickes area

In the temporal lobe, is primarily involved in speech comprehension.

Motor Neurons

Transmit output impulses from the brain and spinal cord to the bodys muscles and organs.

Neurons

Are the basic building blocks of the nervous system.

Cerebral Cortex

A 1 /4- inch- thick sheet of gray (unmyelinated) cells that form the outermost layer of the human brain.

state of tranquility

In general, it slows down body processes and maintains a(n) ________.

Magnetic Resonance Imaging (MRI)

Creates images based on how atoms in living tissue respond to a magnetic pulse delivered by the device.

Autonomic Nervous System

Which senses the body's internal functions and controls the glands and the smooth (involuntary) muscles that form the heart, the blood vessels, and the lining of the stomach and intestines.

Somatic Sensory Cortex

Receives sensory input that gives rise to our sensations of heat, touch, and cold and to our senses of balance and body movement (kinesthesis)

Plasticity in the Brain

The role of experience and the Recovery of Function.

Adrenal Glands

Twin structures perched atop the kidneys that serve, quite literally, as hormone factories, producing and secreting about 50 different hormones.

Excitatory

At synapses involved in muscular movement and memory.