Rapid, reliable mobile assessment of affect-related motor processing

Mobile technologies can be used for behavioral assessments to associate changes in behavior with environmental context and its influence on mental health and disease. Research on real-time motor control with a joystick, analyzed using a computational proportion-derivative (PD) modeling approach, has shown that model parameters can be estimated with high reliability and are related both to self-reported fear and to brain structures important for affective regulation, such as the anterior cingulate cortex. Here we introduce a mobile version of this paradigm, the rapid assessment of motor processing (RAMP) paradigm, and show that it provides robust, reliable, and accessible behavioral measurements relevant to mental health. A smartphone version of a previous joystick sensorimotor task was developed in which participants control a virtual car to a stop sign and stop. A sample of 89 adults performed the task, with 66 completing a second retest session. A PD modeling approach was applied to compute Kp (drive) and Kd (damping) parameters. Both Kp and Kd exhibited high test-retest reliabilities (ICC .81 and .78, respectively). Replicating a previous finding from a different sample with the joystick version of the task, both Kp and Kd were negatively associated with self-reported fear. The RAMP paradigm, a mobile sensorimotor assessment, can be used to assess drive and damping during motor control, which is robustly associated with subjective affect. This paradigm could be useful for examining dynamic contextual modulation of affect-related processing, which could improve assessment of the effects of interventions for psychiatric disorders in a real-world context.

Effectiveness of Paliperidone Depot in Seriously Violent Men With Comorbid Schizophrenia and Dissocial Personality Disorder in a Uk High-Security Hospital

Introduction

High-security hospital patients are often complex in presentation characterised by treatment resistance, medication non-concordance and history of violence. Paliperidone is licensed as both an oral and depot antipsychotic for the treatment of schizophrenia. Whilst there is data for the effectiveness of paliperidone palmitate (PP), there are no studies involving patients in forensic settings or those with comorbid personality disorder.

Objective

To determine the effects of PP on violence, aggression and personality pathology.

Aim

To evaluate the clinical effectiveness of PP.

Methods

This was a retrospective service evaluation involving 11 patients. Medical records and interviews with the treating psychiatrist were used to formulate clinical global impression (CGI) and to identify incidents of violence. The effect on personality symptom domains; cognitive-perceptual, impulsive-behavioural dyscontrol and affective dysregulation was ascertained, as well as engagement with occupational and psychological therapies.

Results

Six patients were being prescribed PP. All 6 showed improvement in the CGI score with benefits in the symptom domains. Two patients demonstrated a reduction in violence risk and 2 remained incident-free. There was improvement in engagement with therapies. Benefits were also seen in aspects of personality for those who had discontinued PP.

Conclusions

This pragmatic study of a small but complex patient group demonstrated that PP was effective in reducing symptoms of schizophrenia. Additionally and for the first time, it was shown that PP was also effective in reducing violence as well as improving personality pathology dimensions in a comorbid patient. This could have significant implications for management of high-security patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Errors leading to unexpected pseudophakic ametropia

PURPOSE

Determination of the reasons for clinically significant unplanned ametropia following cataract surgery and the results of management of the ametropia.

METHODS

Retrospective review of 11 consecutive cases of tertiary referral for management of pseudophakic ametropia to the authors. Corrective surgery involved either lens implant exchange or LASIK refractive surgery. Final outcome was assessed by uncorrected and best spectacle corrected visual acuity and manifest refractive outcome.

RESULTS

Five cases (45%) were due to significant error in axial length determination at pre-surgery biometry. Six cases (55%) were due to surgeon or surgical team error, where the surgeon implanted a lens of power at variance with that specified pre-operatively. Nine patients elected to undergo refractive surgery to correct the ametropia and 2 elected to wear a spectacle lens. Seven underwent lens implant exchange and 2 patients underwent LASIK keratorefractive surgery. Eight of nine patients were within 1 dioptre of intended spherical equivalent after refractive surgery and 1 patients was -1.5 dioptre myopic.

CONCLUSIONS

Most cases of serious unintended ametropia after cataract surgery are avoidable. Care should be taken with the biometry and procedural checks to minimise error. When lens implant exchange or LASIK was performed the final refractive results were satisfactory.

Studies of the borderline between stepwise and concerted mechanisms of elimination: leaving group effects in elimination of (fluoren-9-ylmethyl)-ammonium ions

By comparison with related substrates β-elimination of (fluoren-9-ylmethyl)trimethylammonium ion to form dibenzofulvene in methanolic sodium methoxide is unexpectedly rapid. The reaction has been investigated as a possible example of an E2 mechanism at the borderline between concerted and stepwise reaction paths. Evidence from buffer saturation in dimethylaminoacetonitrile buffers and comparisons with other amine leaving groups suggests, however, that the mechanism is probably ElcB, with ionization to a carbanion intermediate rate-determining. As measured by σ* for the trimethylammonium group the rate of elimination is 105 times faster than predicted from a Taft correlation of rates of carbanion formation. Probably this reflects the sensitivity of substituent constants for monopoles to solvent and reaction, and a rate-enhancing effect from N-methylation of (fluoren-9-ylmethy1)amine. Comparison of the trimethylammonium leaving group with eliminations of neutral amines also confirms an earlier conclusion that intramolecular proton transfer is not an important reaction path in eliminations of amines activated by a β-fluorenyl group.