Neural Communication In the nervous system information moves

Neural Communication In the nervous system, information moves from one place to another via electrical events called nerve impulses. This occurs through the release of chemicals called neurotransmitters. When 1 neuron communicates with another the synapse may occur on a dendrite, on the cell body or along the axon. Synapses between a neuron and another cell type are called neuroeffector junctions. At a synapse between 2 neurons, the impulse passes from the synaptic knob to the postsynaptic neuron. The opposing cell membranes are separated by a narrow space called the synaptic cleft.

Every synaptic vesicle contains several thousand molecules of a specific neurotransmitter and, upon stimulation, many of these vesicles release their contents into the synaptic cleft. There are many different neurotransmitters. Acetylcholine (Ach) is widespread inside and outside of the CNS. It innervates motor neurons and is an internal transmitter for the sympathetic nervous system. Norepinephrine (NE) is important in the brain and the autonomic nervous system. This neurotransmitter is also called the stress hormone and prepares the body for action.

The previous neurotransmitters are considered excitatory. Dopamine, gamma aminobutyric acid (GABA) and serotonin all function in the CNS and are considered inhibitory. Dopamine plays a large role in reward seeking behavior, GABA acts to calm nervous activity and serotonin regulates mood, appetite and sleep and is often manipulated with antidepressant drugs. There at least 50 other neurotransmitters and 2 gases (NO and CO) whose functions are not well understood.

Neurotransmitters Inhibitory Excitatory Dopamine Information Acetylcholine (Ach) Information Gamma aminobutyric acid (GABA) Information Serotonin Information 2 nd Left Side Activity Cut, color and glue the diagram given in class entitled Synapses & Neurotransmitters. 1 st Left Side Activity create a Top Down Flow Chart with the words “Neurotransmitters” at the top. Divide neurotransmitters into excitatory and inhibitory. Then give examples and functions of each from lecture (Example at left). Color the flow chart 4 different colors as at left. Norepinephrine (NE) Information 3 rd Left Side Activity Do 1 other left side activity of your own choice.