Associate Level Material
Appendix C

Brain Response of Behavior

Part I

Note: Parts II and III follow below, complete all three.

Write a 350- to 700-word response to the following: Explain the communication process of neurons in the brain. List some common neurotransmitters and describe their effect on behavior.

Neurons are the microscopic nerve cells of the brain which play a critical role in human behavior and thought processes (Morris & Maisto, 2005). The communication process of neurons begins with the dendrite, short fibers branching from the outer cell body. These dendrites transmit messages to neighboring cells. When a dendrite has received enough information the next step in communication occurs with a nerve impulse, similar to an electrical charge, which sends the information traveling down a single elongated fiber known as an axon. From this point the information continues on until reaching the end of the axon. A terminal button is located at the axon end which then releases neurotransmitters which in turn send the message to the next neuron (Live! Psych, 2002).

Between each neuron is an area known as the synaptic cleft. All messages being transmitted will pass through this tiny space between the terminal button at the end of the sending axon, or presynaptic neuron, and the dendrites or cell body of a receiving, or postsynaptic, neuron (Morris & Maisto, 2005). Inside the terminal button of the presynaptic neuron are tiny sacs known as synaptic vesicles which release chemicals into the synaptic space. The chemicals released are the neurotransmitters. These neurotransmitters will pass through the synaptic cleft prior to being received by the dendrite of a receiving neuron. On the receiving end of the neuron a short period of binding will occur within this receptor site. As receptor sites are made to accept only certain shaped neurotransmitters there may be certain messages which will be unable to be delivered properly should the neurotransmitter and receptor not be a match (Live! Psych, 2002).

There are many types of neurotransmitters and each have a specific effect on the nerve circuit which may either aid or hinder communications. Neurotransmitters which are helpful to the process of communication are known as excitatory. In contrast, the neurotransmitters hindering proper communications are referred to as inhibitory (Live! Psych, 2002). Some of the common neurotransmitters include endorphins, serotonin, and dopamine. Endorphins are small chains of amino acids which aid in the reduction of pain. These neurotransmitters are regularly released during physical exercise and act as a natural pain reducer. Serotonin plays a factor in emotional response and also helps in regulating sleep, mood, and aggressive behavior. Due to serotonins affect on behavior it is commonly referred to as the “mood molecule”. Finally, dopamine is a neurotransmitter which is associated with learning, memory, emotion and voluntary movement (Morris & Maisto, 2005).
Part II

Write a 350- to 700-word response identifying the major regions of the brain and what functions of behavior the systems of each region control.

There are three major regions of the brain known as the central core, the limbic system, and the cerebral cortex. Within these three main regions are various structures which control how an individual behaves as well as body functions (Morris & Maisto, 2005).

The brains central core is where the medulla, pons, cerebellum, thalamus, and hypothalamus are located.. Closest to the point where the spinal cord enters the skull is the medulla which works to control regulating respiration, heart rate and blood pressure. The pons releases chemicals which aid in the regulation of the sleep-wake cycles. Maintaining balance and coordination is the responsibility of the cerebellum which also is commonly referred to as the “little brain”. The brains “relay station” for information is the thalamus. Located