Communication of the Addict Brain Karla Kiecolt-Blasdell Thursday, January 03, 2008 The distinction between physical dependence and addiction is separated using the term physical dependence for a narrower, older definition and the new definition of addiction. Physical dependence is mostly described as a simple cellular adaption of a substance to the body. It especially concen- trates on the neurons as the communication center and the chemical which the brain is influenced by. In contrast, addiction is known to be a complex, lifelong disease of one''s entire self. In studying human brain activity we have learned communication and impulses are carried from one cell to another. There are billions of nerve cells in the brain. These are called neurons. Most neurons have one branch that carry impulses away from the cell body. This branch is called an axon. The outer part of the neuron where the branching of the axon begins is called the dendrite. A single neuron may have as many as 10,000 dendrites. The dendrites then can receive signals from the axons from thousands of different neurons. Simply breaking down how neurons work in the brain focuses on the synapse, the space in the brain where the impulses pass between the cells. The synapse is tiny and continuously active. The activity is affected by both abusive drugs and psychoactive medications. The chemicals enter the bloodstream, pass through the blood-brain barrier and become part of the chemical bath that reaches all the synapses in the brain. Psychoactive externally supplied chemicals inhibit transmission between particular groups of axons and dendrites. Neurons primarily serve excitatory or inhibitory roles in the brain. Abusive drugs fit both of these categories. Amphetamines and cocaine fall into the stimulant category and are primarily excitatory, whereas, alcohol and opiates fall into the depressant category and are primarily inhibitory. Addiction is more than a chemical reaction in the brain. It also relies on three types of behavior-affecting stimuli described by psychologists. They are: positive reinforcement, negative reinforcement, and punishment. A good feeling is positive reinforcement, relief of a painful experience is con- sidered a negative reinforcement. The punishment is a consequence of a negative behavior. All three of these behaviors have direct application to the experience of addiction. Abused drugs directly affect the synapses in the pleasure centers of the brain. There are many activities and substances that impact the pleasure-producing neurons. When referring to addiction it principally involves two features: loss of control (unmanageable), dis- honesty (denial). Without these two features addiction cannot exist. People who are addicted almost act as if they are hypnotized. They cannot tell you why they continue their use of drugs and alcohol despite the negative impact on their lives. Even though the loss over pleasure- driven behaviors is alw... |