LO 1 Define neuroscience and biological psychology and explain their contributions to our understanding of behavior. (p. 48)

Neuroscience is the study of the nervous system and the brain, and it overlaps with a variety of disciplines and research areas. Biological psychology is a subfield of psychology focusing on how the brain and other biological systems influence behavior. These disciplines help us discover connections between behavior and the nervous system (particularly the brain) as well as physiological explanations for mental processes.

LO 2 Compare and contrast tools scientists use to study the brain. (p. 49)

Researchers use a variety of technologies to study the brain. An electroencephalogram (EEG) detects electrical impulses in the brain. Computerized axial tomography (CAT or CT) uses X-rays to create many cross-sectional images of the brain. Magnetic resonance imaging (MRI) uses magnets and pulses of radio waves to produce more detailed cross-sectional images; both MRI and CT scans only reveal the structure of the brain. Positron emission tomography (PET) uses radioactivity to track glucose consumption to construct a map of the brain. Functional magnetic resonance imaging (fMRI) captures changes in brain activity by tracking patterns of blood flow.

LO 3 Label the parts of a neuron and describe an action potential. (p. 52)

A typical neuron has three basic parts: a cell body, dendrites, and an axon. The dendrites receive messages from other neurons, and branches at the end of the axon send messages to neighboring neurons. These messages are electrical and chemical in nature. An action potential is the electrical signal that moves down the axon, causing a neuron to send chemical messages across the synapse. Action potentials are all-or-none, meaning they either fire or do not fire.

LO 4 Illustrate how neurons communicate with each other. (p. 56)

Neurons communicate with each other via chemicals called neurotransmitters. An action potential moves down the axon to the terminal buds, where the command to release neurotransmitters is conveyed. Most of the neurotransmitters released into the synapse drift across the gap and come into contact with receptor sites of the receiving neuron’s dendrites.

LO 5 List various neurotransmitters and summarize their involvement in human behavior. (p. 58)

Neurotransmitters are chemical messengers that neurons use to communicate. There are many types of neurotransmitters, including acetylcholine, glutamate, GABA, norepinephrine, serotonin, dopamine, and endorphins, and each has its own type of receptor site. Neurotransmitters can influence mood, cognition, behavior, and many other processes.

LO 6 Explain how the central and peripheral nervous systems connect. (p. 61)

The brain and spinal cord make up the central nervous system (CNS), which communicates with the rest of the body through the peripheral nervous system (PNS). There are three types of neurons participating in this back-and-forth communication: Motor neurons carry information from the CNS to various parts of the body such as muscles and glands; sensory neurons relay data from the sensory systems (for example, eyes and ears) to the CNS for processing; and interneurons, which reside exclusively in the CNS, act as bridges connecting sensory and motor neurons. Interneurons mediate the nervous system’s most complex operations, including sensory processing, memory, thoughts, and emotions.

LO 7 Describe the organization and function of the peripheral nervous system. (p. 62)

The peripheral nervous system is divided into two branches: the somatic nervous system and the autonomic nervous system. The somatic nervous system controls the skeletal muscles that enable voluntary movement. The autonomic nervous system regulates the body’s involuntary processes and has two divisions: the sympathetic nervous system, which initiates the fight-or-flight response, and the parasympathetic nervous system, which oversees the rest-and-digest processes.

LO 8 Summarize the role of the endocrine system and how it influences behavior. (p. 65)

Closely connected with the nervous system, the endocrine system uses glands to send messages around the body. These messages are conveyed by hormones—chemicals released into the bloodstream that can cause aggression and mood swings, and influence growth and alertness, among other things.

LO 9 Describe the two brain hemispheres and how they communicate. (p. 67)

The cerebrum includes virtually all parts of the brain except for the primitive brainstem structures. It is divided into two hemispheres: the right cerebral hemisphere and the left cerebral hemisphere. The left hemisphere controls most of the movement and sensation on the right side of the body. The right hemisphere controls most of the movement and sensation on the left side of the body. Connecting the two hemispheres is the corpus callosum, a band of fibers that enables them to communicate.

LO 10 Explain lateralization and how split-brain operations affect it. (p. 68)

Each hemisphere excels in certain activities, a phenomenon known as lateralization. The left hemisphere excels in language and the right hemisphere excels in visual-spatial tasks. Under certain experimental conditions, people who have had the split-brain operation act as if they have two separate brains.

LO 11 Identify areas in the brain responsible for language production and comprehension. (p. 71)

Several areas in the brain are responsible for language processing. Broca’s area is primarily responsible for speech production, and Wernicke’s area is primarily responsible for language comprehension.

LO 12 Define neuroplasticity and recognize when it is evident in the brain. (p. 72)

Neuroplasticity is the ability of the brain to form new connections between neurons and adapt to changing circumstances. Networks of neurons, particularly in the young, can reorganize to adapt to the environment and an organism’s ever-changing needs.

LO 13 Identify the lobes of the cortex and explain their functions. (p. 73)

The outermost layer of the cerebrum is the cerebral cortex. The cortex is separated into different sections called lobes. The major function of the frontal lobes is to organize information among the other lobes of the brain. The frontal lobes are also responsible for higher-level cognitive functions, such as thinking and personality characteristics. The parietal lobes receive and process sensory information such as touch, pressure, temperature, and spatial orientation. Visual information goes to the occipital lobes for processing. The temporal lobes are primarily responsible for hearing and language comprehension.

LO 14 Describe the association areas and identify their functions. (p. 77)

The association areas in the lobes integrate information from all over the brain, allowing us to learn, have abstract thoughts, and carry out complex behaviors.

LO 15 Distinguish the structures and functions of the limbic system. (p. 79)

The limbic system is a group of interconnected structures that play an important role in our emotions and memories. The limbic system includes the hippocampus, amygdala, thalamus, and hypothalamus. In addition to processing emotions and memories, the limbic system fuels the most basic drives, such as hunger, sex, and aggression.

LO 16 Distinguish the structures and functions of the brainstem and cerebellum. (p. 80)

The brain’s ancient core consists of a stalklike trio of structures called the brainstem, which includes the midbrain, pons, and medulla. The brainstem extends from the spinal cord to the forebrain, which is the largest part of the brain that includes the cerebral cortex and the limbic system. Located at the top of the brainstem is the midbrain, which most agree plays a role in levels of arousal. The hindbrain includes areas responsible for fundamental life-sustaining processes. Behind the brainstem is the cerebellum, which is responsible for muscle coordination and balance.