Erratum: Neurocircuitry of Addiction

Abstract

Drug addiction is a chronically relapsing disorder that has been characterized by (1) compulsion to seek and take the drug, (2) loss of control in limiting intake, and (3) emergence of a negative emotional state (eg, dysphoria, anxiety, irritability) reflecting a motivational withdrawal syndrome when access to the drug is prevented. Drug addiction has been conceptualized as a disorder that involves elements of both impulsivity and compulsivity that yield a composite addiction cycle composed of three stages: 'binge/intoxication', 'withdrawal/negative affect', and 'preoccupation/anticipation' (craving). Animal and human imaging studies have revealed discrete circuits that mediate the three stages of the addiction cycle with key elements of the ventral tegmental area and ventral striatum as a focal point for the binge/intoxication stage, a key role for the extended amygdala in the withdrawal/negative affect stage, and a key role in the preoccupation/anticipation stage for a widely distributed network involving the orbitofrontal cortex-dorsal striatum, prefrontal cortex, basolateral amygdala, hippocampus, and insula involved in craving and the cingulate gyrus, dorsolateral prefrontal, and inferior frontal cortices in disrupted inhibitory control. The transition to addiction involves neuroplasticity in all of these structures that may begin with changes in the mesolimbic dopamine system and a cascade of neuroadaptations from the ventral striatum to dorsal striatum and orbitofrontal cortex and eventually dysregulation of the prefrontal cortex, cingulate gyrus, and extended amygdala. The delineation of the neurocircuitry of the evolving stages of the addiction syndrome forms a heuristic basis for the search for the molecular, genetic, and neuropharmacological neuroadaptations that are key to vulnerability for developing and maintaining addiction.

Histone-Mediated Epigenetics in Addiction

“…The first time drugs of abuse are used (e.g., psychostimulants, alcohol, opioids, nicotine, Δ 9 tetrahydro-cannabinol), brain regions in both reward (i.e., ventral tegmental area, striatum, nucleus accumbens core, thalamus) and learning (basolateral and central nucleus of the amygdala, medial prefrontal cortex, hippocampus) centers share excitatory information (reviewed in Koob & Volkow 2010; Marchant et al, 2012). Some of these structures serve a primary role in particular stages of addiction (e.g., binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation/craving; Koob & Volkow, 2010) and memory processes (i.e., encoding, consolidation, and retrieval; e.g., Bernardi et al, 2009; Lalumiere et al, 2012), yet many of these regions can be recruited throughout each process. Importantly, the circuits mediating aspects of reward and aspects of memory overlap, with key processes in the amygdala, ventral tegmental area (VTA), and nucleus accumbens (NAc) controlling consolidation of these drug memories.…”

“…There are important similarities in the systems and molecular steps that are involved in initial memory formation and extinction (e.g., Lattal et al, 2006), but there also are critical differences. For example, initial memory formation and extinction may recruit specific and distinct subregions of the medial prefrontal cortex, amygdala, and nucleus accumbens (e.g., Koob & Volkow 2010; Peters et al, 2009; Stefanik et al, 2013; Tye et al, 2010). It is thought that these excitatory and inhibitory circuits are usurped during the transition from drug use to eventual addiction (e.g., Hyman 2005) and modulate inhibition of drug-seeking behavior during extinction or abstinence.…”

Development of a Mobile Phone Addiction Craving Scale and Its Validation in a Spanish Adult Population

“…To put simply, craving can be defined as an unstoppable and uncontrollable desire that can lead to use (a drug, a technology), despite its negative and detrimental effects. This impulsive loss-of-control can lead to a search for gratification or positive reinforcement or turn into a compulsion whose objective would be to avoid distress or dysphoria, a negative reinforcement that would sustain the abnormal use (12). …”

“…Thus, craving would arise as much from internal stimuli, such as feelings and thoughts, as from external or environmental stimuli. It also differs depending on the type of substance or drug (12, 13), in which cravings for cocaine or alcohol would not be the same. In all likelihood, in behavioral addictions, a different craving must exist among the behaviors.…”

Addiction, Chronic Illness, and Responsibility

“…Patients with compulsive disorders feel great anxiety and stress before committing the compulsive act and then relief from the stress after performing the act (cf. Koob and Volkow 2010). (This contrasts with impulsive behaviors, which are linked to positive reinforcement: impulsive patients feel tension or arousal before committing the impulsive act and then pleasure or gratification after).…”