The insular cortex and addiction: a new insight into therapeutic potential for addiction& bipolar disorder

Background and Aim : The insula lies deep in the floor of the lateral fissure ,and overlapped by a operculum .Cytoarchitectonically, three zones are recoginized within the insula. Anteriorly,the cortex is granular which surrounded by a belt of dysgranular cortex ,the posterior part of insular cortex is granular regions .The Insula has connections with cingulate gyrus, amygdale, basal ganglia, brain stem ,thalamus and parietal ,frontal, temporal lobes. According these connection, Insula involved in the integration of pain, viscerosensory, visceromotor , cognitive ,auditory , speech , self awareness, limbic and autonomic function.Methods : This paper reviews the foundation for a role of the human anterior insular cortex (AIC) in addiction.Results : The classical literature on the neurobiology of addiction has focused mainly on the subcortical system , such as the amygdala, the ventral striatum and mesolimbic system. However, recent evidence have supported the notion that addiction is regulated by cortical modulation. In additionally, studies indicates that AIC plays a crucial part in conscious usage of drugs. The neurotransmitter & receptors of the insula supports its role in motivation, emotion and addiction. AIC receives dopaminergic innervation , contains a high concentration of opioids and corresponding receptors. These receptors can have a role in use of drugs,pain ,neural plasticity and therapeutic potential for addiction.lesion studies on the function of insular indicated that damage to the insula disrupts addiction to cigarette smoking. Nicotine, cannabis , heroin, methamphetamine, cocaine , and alcohol have been shown to cause structural changes to the insula.Drug users had gray matter reductions in the insula. The duration of drug use was associated with changes gray matter in insula. Also, In bipolar disorder gray matter reduce in anterior cingulated gyrus and insula that regions implicated in emotional processing.Conclusion : The insula may be involved in therapeutic potential for addiction & bipolar disorder.

کلیدواژه ها:

insular cortex ، addiction ، bipolar disorder