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Is “Maybe” Addictive?
Louise Stapleton-Frappell examines the roles of dopamine, anticipation, and reinforcement
schedules and the essential roles they combine to play in the efficacy of your training
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© Can Stock Photo/damedeeso
Although dopamine has “an accepted role” in reward processing, there has been “considerable debate over the role of phasic dopamine activity in processing non-rewarding events,” according to Bromberg-Martin, Matsumoto & Hikosaka (2010)
he monoamine neurotransmitter dopamine plays several important roles in the brain and the body, affecting emotions, movements and sensations of pleasure and pain. It also plays a role in many functions, such as memory, lactation, attention, sleep regulation, arousal, motivation, and movement (Berndt, 2002). Dopamine neurons are concentrated in several areas of the brain, the largest being the substantia nigra and ventral tegmental area in the midbrain. Other areas include the hypothalamus, olfactory bulb, and retina. Dopamine from the substantia nigra helps begin movements and speech – deficiencies play a role in disorders such as Parkinson’s disease – while dopamine from the ventral tegmental area is released into the brain when animals expect or receive a reward, helping them “change 18
BARKS from the Guild/November 2018
their behaviors in ways that will help them attain more of the rewarding item or experience.”(Brookshire, 2017). Dopamine motivates animals to repeat an action. Also, drugs such as cocaine, nicotine and heroin cause dopamine levels to spike and can lead to addiction as the user seeks out the “reward.” In operant conditioning, behavioral responses that are positively reinforced increase in frequency, intensity or duration. The cue is given, the response occurs, reinforcement follows and the loop is repeated. One would perhaps expect dopamine levels to rise upon receipt of the reinforcer. But do they? Some studies have shown that increases in dopamine are not, in fact, directly related to the reinforcer. Rather, it is the anticipation of the reinforcer that causes dopamine levels to spike. Although dopamine sig-