Apathy and Impulse Control Disorders: Yin & Yang of Dopamine Dependent Behaviors.

Neuropsychiatric symptoms are common non-motor symptoms in Parkinson's disease (PD). Apathy and impulse control disorders (ICD) are two opposite motivational expressions of a continuous behavioural spectrum involving hypo- and hyperdopaminergia. Both syndromes share pathological (decreased vs increased) dopamine receptor stimulation states. Apathy belongs to the spectrum of hypodopaminergic symptoms together with anhedonia, anxiety and depression. Apathy is a key symptom of PD which worsens with disease progression. Animal models, imaging and pharmacological studies concur in pointing out dopaminergic denervation in the aetiology of parkinsonian apathy with a cardinal role of decreased tonic D2/D3 receptor stimulation. ICDs are part of the hyperdopaminergic behavioural spectrum, which also includes punding, and dopamine dysregulation syndrome (DDS), which are all related to non-physiological dopaminergic stimulation induced by antiparkinsonian drugs. According to clinical data tonic D2/D3 receptor stimulation can be sufficient to induce ICDs. Clinical observations in drug addiction and PD as well as data from studies in dopamine depleted rodents provide hints allowing to argue that both pulsatile D1 and D2 receptor stimulation and the severity of dopaminergic denervation are risk factors to develop punding behavior and DDS. Imaging studies have shown that the brain structures involved in drug addiction are also involved in hyperdopaminergic behaviours with increase of bottom-up appetitive drive and decrease in prefrontal top down behavioural control.

Effects of mindful eating training on delay and probability discounting for food and money in obese and healthy-weight individuals.

Obese individuals tend to behave more impulsively than healthy weight individuals across a variety of measures, but it is unclear whether this pattern can be altered. The present study examined the effects of a mindful eating behavioral strategy on impulsive and risky choice patterns for hypothetical food and money. In Experiment 1, 304 participants completed computerized delay and probability discounting tasks for food-related and monetary outcomes. High percent body fat (PBF) predicted more impulsive choice for food, but not small-value money, replicating previous work. In Experiment 2, 102 randomly selected participants from Experiment 1 were assigned to participate in a 50-min workshop on mindful eating or to watch an educational video. They then completed the discounting tasks again. Participants who completed the mindful eating session showed more self-controlled and less risk-averse discounting patterns for food compared to baseline; those in the control condition discounted similarly to baseline rates. There were no changes in discounting for money for either group, suggesting stimulus specificity for food for the mindful eating condition.

A randomized controlled trial of a novel self-help technique for impulse control disorders: a study on nail-biting.

Nail-biting is currently classified as an impulse control disorder not otherwise specified. Although seldom targeted as a primary symptom, nail-biting is often associated with somatic complications and decreased quality of life. The present study assessed the effectiveness of an innovative self-help technique, titled decoupling (DC). DC aims at attenuating pathological nail-biting by performing motor sequences that decouple and rearrange the behavioral elements involved in the habit. A total of 72 participants with excessive nail-biting were recruited via specialized self-help forums and were randomized to either DC or progressive muscle relaxation (PMR) groups after baseline assessment. Four weeks later, participants underwent a similar assessment as before and were asked to rate the effectiveness of the intervention. The primary outcome parameter was the Massachusetts General Hospital Scale (MGH) adapted. Relative to the PMR group, the DC group showed significant progress in withstanding the urge to bite their nails. Furthermore, they appraised the appearance of their nails as considerably less compromised at the end of the treatment relative to participants undergoing PMR. At statistical trend level, the DC group showed a significantly greater decline on the adapted MGH relative to PMR. Despite methodological limitations, the present study asserts that the effectiveness of DC, previously shown for trichotillomania, extends to nail-biting.

The manipulation of arousal on the intensity of urges to pull hair in a 16 year old female with trichotillomania: a single case study.

Hairpulling (trichotillomania) is often linked to stressful circumstances and may produce feelings of guilt, shame and humiliation. In a behavioural model, affective experience was identified as an important maintaining factor, as both a cue and reinforcer. Habit Reversal is one of the more successful behavioural treatment options. The present study evaluated the role of emotional arousal in the intensity of urges to pull hair in a teenaged patient with trichotillomania. Using an experimental ABCD/DCBA reversal design, the patient used imagery to increase her emotional arousal through the presentation of a manipulation script based on her own experience, after baseline and during a rumination, cognitive and a behavioural distraction phase. Subjective measures of urge intensity were collected at five time points during completion of a task, and a tally was made of an overt hair touching behaviour operationalized as a hairpulling substitute behaviour. The patient experienced more intense urges to pull whilst ruminating on the arousal script compared to either of the distraction phases. The findings support the view that the experience of negative emotional arousal can exacerbate and intensify the experience of urges to pull hair in patients with trichotillomania, and that both cognitive and behavioural distraction techniques have some effect in controlling them. Demonstrating this to the patient aided engagement in treatment.

Sexual predators.

Social responses to sex-offending behaviors have included criminal sanctions and clinical interventions that have evolved over time. These developments have created various challenges for mental health professionals charged with providing care to offenders, particularly when legislative expectations have exceeded available treatments. A summary is provided of recent clinical developments in assessments, therapies, and pharmacology. The usefulness of SRIs, in particular, may prompt the involvement of more psychiatrists in this treatment. Other implications for future practice of these clinical and legal developments are also discussed.