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La dopamina es una hormona que te relaja? Vos sabes que es la dopamina o estas inventando?
Learning, reinforcement, and reward-seeking behavior
Dopamine is commonly associated with the reward system of the brain, providing feelings of enjoyment and reinforcement to motivate a person to perform certain activities. Dopamine is released (particularly in areas such as the nucleus accumbens and prefrontal cortex) by rewarding experiences such as food, sex, drugs, and neutral stimuli that become associated with them.[38] Recent studies indicate that aggression may also stimulate the release of dopamine in this way.[39]
This theory can be discussed in terms of drugs such as cocaine, nicotine, and amphetamines, which directly or indirectly lead to an increase of dopamine in the mesolimbic reward pathway of the brain, and in relation to neurobiological theories of chemical addiction (not to be confused with psychological dependence), arguing that this dopamine pathway is pathologically altered in addicted persons.[40] In recent studies, cholinergic inactivation of the nucleus accumbens was able to disrupt the acquisition of drug reinforced behaviors, suggesting that dopamine has a more limited involvement in the acquisition of both drug self-administration and drug-conditioned place-preference behaviors than previously thought.[41][42]
Dopaminergic neurons of the midbrain are the main source of dopamine in the brain.[38] Dopamine has been shown to be involved in the control of movements, the signaling of error in prediction of reward, motivation, and cognition. Cerebral dopamine depletion is the hallmark of Parkinson's disease.[38] Other pathological states have also been associated with dopamine dysfunction, such as schizophrenia, autism, and attention deficit hyperactivity disorder, as well as drug abuse.
Dopamine is closely associated with reward-seeking behaviors, such as approach, consumption, and addiction.[38] Recent researches suggest that the firing of dopaminergic neurons is a motivational substance as a consequence of reward-anticipation. This hypothesis is based on the evidence that, when a reward is greater than expected, the firing of certain dopaminergic neurons increases, which consequently increases desire or motivation towards the reward.[38] However, recent research finds that while some dopaminergic neurons react in the way expected of reward neurons, others do not and seem to respond in regard to unpredictability.[43] This research finds the reward neurons predominate in the ventromedial region in the substantia nigra pars compacta as well as the ventral tegmental area. Neurons in these areas project mainly to the ventral striatum and thus might transmit value-related information in regard to reward values.[43] The nonreward neurons are predominate in the dorsolateral area of the substantia nigra pars compacta which projects to the dorsal striatum and may relate to orienting behaviour.[43] It has been suggested that the difference between these two types of dopaminergic neurons arises from their input: reward-linked ones have input from the basal forebrain, while the nonreward-related ones from the lateral habenula.[43]