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Impulsivity and compulsivity have been implicated as important transdiagnostic dimensional phenotypes with potential relevance to addiction. We aimed to develop a model that conceptualizes these constructs as overlapping dimensional phenotypes and test whether different components of this model explain the co-occurrence of addictive and related behaviors.
A large sample of adults (N = 487) was recruited through Amazon’s Mechanical Turk and completed self-report questionnaires measuring impulsivity, intolerance of uncertainty, obsessive beliefs, and the severity of 6 addictive and related behaviors. Hierarchical clustering was used to organize addictive behaviors into homogenous groups reflecting their co-occurrence. Structural equation modeling was used to evaluate fit of the hypothesized bifactor model of impulsivity and compulsivity and determine the proportion of variance explained in the co-occurrence of addictive and related behaviors by each component of the model.
Addictive and related behaviors clustered into 2 distinct groups: Impulse-Control Problems, consisting of harmful alcohol use, pathological gambling, and compulsive buying, and Obsessive-Compulsive-Related Problems, consisting of obsessive-compulsive symptoms, binge eating, and internet addiction. The hypothesized bifactor model of impulsivity and compulsivity provided the best empirical fit, with 3 uncorrelated factors corresponding to a general Disinhibition dimension, and specific Impulsivity and Compulsivity dimensions. These dimensional phenotypes uniquely and additively explained 39.9% and 68.7% of the total variance in Impulse-Control Problems and Obsessive-Compulsive-Related Problems.
A model of impulsivity and compulsivity that represents these constructs as overlapping dimensional phenotypes has important implications for understanding addictive and related behaviors in terms of shared etiology, comorbidity, and potential transdiagnostic treatments.
Understanding the relative risks of maintenance treatment versus discontinuation of antipsychotics following remission in first episode psychosis (FEP) is an important area of practice.
A systematic review and meta-analysis. Prospective experimental studies including a parallel control group were identified to compare maintenance antipsychotic treatment with total discontinuation or medication discontinuation strategies following remission in FEP.
Seven studies were included. Relapse rates were higher in the discontinuation group (53%; 95% CIs: 39%, 68%; N = 290) compared with maintenance treatment group (19%; 95% CIs: 0.05%, 37%; N = 230). In subgroup analyses, risk difference of relapse was lower in studies with a longer follow-up period, a targeted discontinuation strategy, a higher relapse threshold, a larger sample size, and samples with patients excluded for drug or alcohol dependency. Insufficient studies included psychosocial functioning outcomes for a meta-analysis.
There is a higher risk of relapse for those who undergo total or targeted discontinuation strategies compared with maintenance antipsychotics in FEP samples. The effect size is moderate and the risk difference is lower in trials of targeted discontinuation strategies.
Declaration of interest
A.T. has received honoraria and support from Janssen-Cilag and Otsuka Pharmaceuticals for meetings and has been has been an investigator on unrestricted investigator-initiated trials funded by AstraZeneca and Janssen-Cilag. He has also previously held a Pfizer Neurosciences Research Grant. S.M. has received sponsorship from Otsuka and Lundbeck to attend an academic congress and owns shares in GlaxoSmithKline and AstraZeneca. J.H. has attended meetings supported by Sunovion Pharmaceuticals.
We aimed to determine whether individuals with obsessive-compulsive disorder (OCD) and demographically matched healthy individuals can be clustered into distinct clinical subtypes based on dimensional measures of their self-reported compulsivity (OBQ–44 and IUS–12) and impulsivity (UPPS–P).
Participants (n=217) were 103 patients with a clinical diagnosis of OCD; 79 individuals from the community who were “OCD-likely” according to self-report (Obsessive-Compulsive Inventory–Revised scores equal or greater than 21); and 35 healthy controls. All data were collected between 2013 and 2015 using self-report measures that assessed different aspects of compulsivity and impulsivity. Principal component analysis revealed two components broadly representing an individual's level of compulsivity and impulsivity. Unsupervised clustering grouped participants into four subgroups, each representing one part of an orthogonal compulsive-impulsive phenotype.
Clustering converged to yield four subgroups: one group low on both compulsivity and impulsivity, comprised mostly of healthy controls and demonstrating the lowest OCD symptom severity; two groups showing roughly equal clinical severity, but with opposing drivers (i.e., high compulsivity and low impulsivity, and vice versa); and a final group high on both compulsivity and impulsivity and recording the highest clinical severity. Notably, the largest cluster of individuals with OCD was characterized by high impulsivity and low compulsivity. Our results suggest that both impulsivity and compulsivity mediate obsessive-compulsive symptomatology.
Individuals with OCD can be clustered into distinct subtypes based on measures of compulsivity and impulsivity, with the latter being found to be one of the more defining characteristics of the disorder. These dimensions may serve as viable and novel treatment targets.
Acute alcohol consumption is a major risk factor for suicide, therefore
investigating factors associated with alcohol-related self-harm warrant
To investigate the influence of prescribed psychotropic medications on
the odds of co-ingesting alcohol preceding or during intentional efforts
A cross-sectional analysis of consecutive hospital presentations
following intentional self-poisoning was conducted. A total of 7270
patients (4363 women) aged 18–96 were included.
The odds of alcohol co-ingestion were increased in those not prescribed
any medication (odds ratio (OR) = 1.27, 99% CI 1.10–1.46, P50.001) and in
impulsive self-poisonings (OR= 1.39, 99% CI 1.11–1.74, P50.001). Odds
were decreased in those prescribed anticonvulsants (OR = 0.69, 99% CI
0.51–0.93), antipsychotics (OR = 0.55, 99% CI 0.45–0.66) and
antidepressants (OR = 0.87, 99% CI 0.77–0.99).
Findings indicate that being medicated for a psychiatric illness may
reduce the likelihood of alcohol consumption during times of acute
distress, hence perhaps may reduce the risk of intentional
In 1890, William Sellers, leader of Philadelphia's mechanical community, signaled the end of the nineteenth-century system of workshop apprenticeship. Speaking before the Engineers’ Club he declared that “The crafts which once supplied the comforts and even the luxuries of life have been so divided and subdivided, that few masters of an art… could now find the occasion to practice it; the system of apprenticeship, which had theretofore provided a succession of skilled workmen, became impracticable with the vast army that required to be taught the special details of an art only.” The search for an alternative system started in the 1870s as owners of advanced machine works contemplated a horrifying world in which the city's youth roamed free without the steadying hand of an employer or grounding in vocational skills. In 1878 the Baldwin Locomotive Works, in association with the Spring Garden Institute, pioneered a new system of industrial training—a radical departure from nineteenth-century apprenticeship. Apprentices received instruction in the full range of manual skills from an experienced journeyman on the shop floor but, with the new system, training took place in the shop and classroom under the direct charge of the firm. Sociologist Harry Braverman suggested that the division of labor under industrial capitalism split the work of skilled mechanics by separating conception and execution of tasks. In the sphere of education, a parallel force led to the demise of apprenticeship and the triumph of industrial training. The classroom conquered the workshop.
To determine the rates and associated illness characteristics of obsessive-compulsive disorder (OCD) patients who describe their symptoms as either rewarding or habitual.
Seventy-three treatment-seeking OCD patients had their dominant compulsive behavior assessed with a structured interview (the Temporal Impulsive-Compulsive Scale–Revised) to track the progression of rewarding (ie, gain in positive affect), aversive (ie, decrease in negative affect), and neutral (or non-affective) states and a self-report scale (the Self-Report Habit Index) to evaluate their habitual features. Additional measures included structured diagnostic interviews for axis I and II disorders, measures of OCD symptoms severity, and a battery of instruments to comprehensively assess relevant aspects of sensitivity to reward and fear.
Almost half (49%) of our OCD patients (particularly washers) endorsed that they anticipated obtaining a reward (ie, positive affect) from the enactment of their dominant compulsive behavior. Washers stood out in that their positive affects during and after compulsive behaviors were highly (and positively) correlated with duration of illness. In contrast, habit strength did not differ between washers, checkers, and arrangers, although it also correlated with duration of illness among checkers. Furthermore, the severity of OCD and comorbidity with impulse control disorders predicted up to 35% of the variance in the habit strength of OCD behaviors.
Compulsive washing may be more clearly characterized by problems in reward processing. In contrast, duration of checking, severity of OCD, and comorbidity with impulse control disorders shape compulsive behaviors by imparting them with habitual tendencies.
Impulse control disorders (ICDs) have become a widely recognized non-motor complication of Parkinson's disease (PD) in patients taking dopamine replacement therapy (DRT). There are no current evidence-based recommendations for their treatment, other than reducing their dopaminergic medication.
This study reviews the current literature of the treatment of ICDs including pharmacological treatments, deep brain stimulation, and psychotherapeutic interventions.
Dopamine agonist withdrawal is the most common and effective treatment, but may lead to an aversive withdrawal syndrome or motor symptom degeneration in some individuals. There is insufficient evidence for all other pharmacological treatments in treating ICDs in PD, including amantadine, serotonin selective reuptake inhibitors, antipsychotics, anticonvulsants, and opioid antagonists (e.g. naltrexone). Large randomized control trials need to be performed before these drugs can be routinely used for the treatment of ICDs in PD. Deep brain stimulation remains equivocal because ICD symptoms resolve in some patients after surgery but may appear de novo in others. Cognitive behavioral therapy has been shown to improve ICD symptoms in the only published study, although further research is urgently needed.
Further research will allow for the development of evidence-based guidelines for the management of ICDs in PD.
Ground-state OH masers identified in the Southern Parkes Large-Area Survey in Hydroxyl were observed with the Australia Telescope Compact Array to obtain positions with high accuracy (~1 arcsec). We classified these OH masers into evolved star OH maser sites, star formation OH maser sites, supernova remnant OH maser sites, planetary nebula OH maser sites and unknown maser sites using their accurate positions. Evolved star and star formation OH maser sites in the Galactic Centre region (between Galactic longitudes of −5° to +5° and Galactic latitudes of −2° and +2°) were studied in detail to understand their distributions.
Past research suggests that although political violence in mature democracies is rare, it does occasionally occur along ethnic, religious, and/or linguistic lines. Jamaica is an exceptional case in that it is a relatively mature democracy that experiences political violence between demographically similar groups. This article examines the origins of political violence in Jamaica—that is, the conditions that led to its development, intensification, and institutionalization during the late colonial period. Through original archival research, this article supports past findings identifying personality politics, the politicization of race/class divisions, and clientelism as contributing factors to the development of political violence. The research also, however, makes a major new contribution by providing evidence that colonial nonintervention during the early stages of political violence was a crucial factor leading to its escalation and then institutionalization. This finding gives the British colonial state a different and more central role than the extant literature suggests and has broader implications for all democracies.
The Folkton ‘Drums’ constitute three of the most remarkable decorated objects from Neolithic Britain. New analysis using Reflectance Transformation Imaging and photogrammetry has revealed evidence for previously unrecorded motifs, erasure and reworking. Hence these chalk drums were not decorated according to a single, pre-ordained scheme, but were successively carved and recarved over time. Such practices may have been widespread in the making of artefacts in Neolithic Britain. The study of these drums also demonstrates the ability of these new techniques not only to record visible motifs, but to document erased and reworked motifs clearly.
We present results from a Mopra 7 mm-wavelength survey that targeted the dense gas-tracing CS(1-0) transition towards the young γ-ray-bright supernova remnant, RX J1713.7–3946 (SNR G 347.3−0.5). In a hadronic γ-ray emission scenario, where cosmic ray (CR) protons interact with gas to produce the observed γ-ray emission, the mass of potential CR target material is an important factor. We summarise newly discovered dense gas components, towards Cores G and L, and Clumps N1, N2, N3, and T1, which have masses of 1 – 104 M⊙. We argue that these components are not likely to contribute significantly to γ-ray emission in a hadronic γ-ray emission scenario. This would be the case if RX J1713.7–3946 were at either the currently favoured distance of ~1 kpc or an alternate distance (as suggested in some previous studies) of ~6 kpc.
This survey also targeted the shock-tracing SiO molecule. Although no SiO emission corresponding to the RX J1713.7–3946 shock was observed, vibrationally excited SiO(1-0) maser emission was discovered towards what may be an evolved star. Observations taken 1 yr apart confirmed a transient nature, since the intensity, line-width, and central velocity of SiO(J = 1-0,v = 1,2) emission varied significantly.
Repetition of hospital-treated self-poisoning and admission to
psychiatric hospital are both common in individuals who self-poison.
To evaluate efficacy of postcard intervention after 5 years.
A randomised controlled trial of individuals who have self-poisoned:
postcard intervention (eight in 12 months) plus treatment as usual
v. treatment as usual. Our primary outcomes were
self-poisoning admissions and psychiatric admissions (proportions and
There was no difference between groups for any repeat-episode
self-poisoning admission (intervention group: 24.9%, 95% CI 20.6-29.5;
control group: 27.2%, 95% CI 22.8-31.8) but there was a significant
reduction in event rates (incidence risk ratio (IRR)=0.54, 95% CI
0.37-0.81), saving 306 bed days. There was no difference for any
psychiatric admission (intervention group: 38.1%, 95% CI 33.1-43.2;
control group: 35.5%, 95% CI 30.8-40.5) but there was a significant
reduction in event rates (IRR=0.66, 95% CI 0.47-0.91), saving 2565 bed
A postcard intervention halved self-poisoning events and reduced
psychiatric admissions by a third after 5 years. Substantial savings
occurred in general hospital and psychiatric hospital bed days.
A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (H i) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey will study the distribution of H i emission and absorption with unprecedented angular and velocity resolution, as well as molecular line thermal emission, absorption, and maser lines. The area to be covered includes the Galactic plane (|b| < 10°) at all declinations south of δ = +40°, spanning longitudes 167° through 360°to 79° at b = 0°, plus the entire area of the Magellanic Stream and Clouds, a total of 13 020 deg2. The brightness temperature sensitivity will be very good, typically σT≃ 1 K at resolution 30 arcsec and 1 km s−1. The survey has a wide spectrum of scientific goals, from studies of galaxy evolution to star formation, with particular contributions to understanding stellar wind kinematics, the thermal phases of the interstellar medium, the interaction between gas in the disk and halo, and the dynamical and thermal states of gas at various positions along the Magellanic Stream.
A series of very wide (up to 15 km) raised shore platforms in the Scottish Hebrides are identified and described for the first time and are considered part of a high rock platform shoreline in the western isles of Scotland described by W. B. Wright in his classic Geological Magazine paper a century ago as a ‘preglacial’ feature. Subsequent interpretations suggesting that the platforms were produced during the Pleistocene are rejected here in favour of a speculative hypothesis that the features are part of the well-known strandflat that is extensively developed across large areas of the northern hemisphere. It is argued that the Scottish strandflat developed during the Pliocene and was later subjected to extensive Pleistocene glacial erosion such that only a few areas of platform have survived in the Scottish Inner Hebrides (ice-proximal) while they are well-preserved in the Outer Hebrides (ice-distal). Support for a Pliocene hypothesis is provided by the marine oxygen isotope record for this time interval which points to prolonged periods of relative sea level stability as would be required for the production of such wide features. This hypothesis for the formation of a Scottish strandflat not only provides an elegant explanation for the origin and age of the raised rock platform fragments that occur throughout the western isles of Scotland, but it may also have relevance for other coastal areas of the northern hemisphere (e.g. Norway, Greenland, Alaska) where the strandflat is a well-developed feature.
To ascertain the views and experiences of psychiatrists in England and Wales regarding community treatment orders (CTOs). We mailed 1928 questionnaires to members of the Royal College of Psychiatrists.
In total, 566 usable surveys were returned, providing a 29% response rate. Respondents were generally positive about the introduction of the new powers, more so than in previous UK studies. They reported that their decision-making regarding compulsion was based largely on clinical grounds.
In the absence of research evidence or a professional consensus about the use of CTOs, multidisciplinary input in decision-making is essential. Further research and training are urgently needed.
Ensembles of indium phosphide nanowires were grown on amorphous quartz substrates and their optical properties were examined at various cryogenic temperatures. Complex dynamics result from the large areal densities, random orientation, combination of both zincblende and wurtzite phases, and the geometries of the nanowires. Those complex dynamics are discussed in relation to their effect on the temperature dependence of photoluminescence and Raman spectroscopy. Five peaks are found to exist in the photoluminescence spectra at low temperatures which are attributed to radiative recombinations associated with quantum confined zinc blende, quantum confined excitons in zinc blende, quantum confined wurtzite, excitons in bulk zinc blende and impurity states. An energy transfer mechanism between two types of radiative recombinations among the five is proposed to explain intensity variations and the temperature dependence of the PL peaks is discussed. The Raman spectra is observed to have peaks created by a combination of zinc blende and wurtzite vibrational modes which is explained by folding the phonon dispersion.