Virtual reality cognitive & functional assessment in psychosis

AimsTo compare the MATRICS Consensus Cognitive Battery (MCCB) and a novel Virtual Reality (VR) task, called VStore, in assessing cognition and functional capacity (FC) in schizophrenia. We hypothesise that VStore reliably discriminates between patients and controls, correlates with the MCCB, and is well-tolerated. Additionally, VStore is expected to strongly correlate with FC measures.BackgroundCognitive and functional deficits in schizophrenia have a major impact on everyday functioning of patients. The gold-standard cognitive assessment is the MCCB, while the USCD Performance-Based Skills Assessment (UPSA) is used to assess FC in this patient group. Neither of which are without limitations. For example, both take a long time to administer, and the MCCB alone cannot give clear indications of FC. We propose the use of a novel VR task to simultaneously measure cognition and FC in a single assessment. VStore is a shopping task, which involves a verbal learning task followed by buying items from a predetermined shopping list in a virtual minimarket.MethodTen patients with schizophrenia or schizoaffective disorder and ten age/gender-matched healthy controls recruited from South London, completed the following assessments: VStore, MCCB, UPSA & Global Assessment of Functioning (GAF), and VR-Symptom Questionnaire (VRSQ); while controls only completed the VR task. To test whether VStore can differentiate between patients and controls we employed unpaired t-test. To explore associations between VStore Total Time, MCCB composite score and FC measures Pearson's r was used. Finally, mean differences between pre/post-VR symptoms scores were tested using paired t-test.ResultThere was a significant difference between patients and controls on the verbal learning task (t16.38=−4.67,p < .001), and total time spent completing the VR task (t11.41 = 2.67, p = .023). In addition, VStore had a strong association with MCCB composite score (r=−.80,p = .010). While both VStore (r=−.82, p < 001) and MCCB (r = .77,p = .010) had significant correlation with the UPSA, only VStore had a significant association with the GAF (r=−.68,p = .030). Finally, VStore appears to be well-tolerated, causing no measurable side effects in the VRSQ (Pre-VR Mean =12.1[SD = 13.5], Post-VR Mean = 9.6[SD = 11.5],t9 = 0.49,p > .05).ConclusionResults suggest that VStore can discriminate between schizophrenia patients and healthy controls. In addition, VStore and MCCB seem to be strongly associated, suggesting that they tap into identical cognitive domains. VStore seems to be strongly correlated with FC, more so than the MCCB, and cause no measurable side effects. Taken together, this suggests that this novel VR task has the potential to reliably measure cognition and FC simultaneously.

No interaction between rivastigmine and citalopram on memory and novelty processing in healthy human volunteers

Background: Animal literature suggests an interaction between acetylcholine and serotonin on cognitive functions. Aims: The aim of the current study was to assess whether both neurotransmitters interact during memory and novelty processing in humans. Methods: We tested the interaction between acetylcholine and serotonin on cognitive functions in healthy volunteers by means of treatment with rivastigmine and citalopram, respectively. Results: The main result of the study showed that during the verbal learning task participants significantly recalled fewer words after citalopram treatment than after rivastigmine or placebo during both the immediate and delayed recall tasks. Rivastigmine was not able to reverse the impairing effect of citalopram. Conclusions: This finding is in line with previous studies in which we manipulated acetylcholine and serotonin in different manners. Taken together, these studies in humans do not support the notion from animal studies that these two neurotransmitters interact on cognitive functions.

Lutein and Zeaxanthin Influence Brain Function in Older Adults: A Randomized Controlled Trial

Objectives:The present study constitutes the first randomized controlled trial to investigate the relation of lutein (L) and zeaxanthin (Z) to brain function using functional magnetic resonance imaging (fMRI). It was hypothesized that L and Z supplementation in older adults would enhance neural efficiency (i.e., reduce activation) and cognitive performance on a verbal learning task relative to placebo.Methods:A total of 44 community-dwelling older adults (mean age=72 years) were randomly assigned to receive either placebo or L+Z supplementation (12 mg/daily) for 1 year. Neurocognitive performance was assessed at baseline and post-intervention on an fMRI-adapted task involving learning and recalling word pairs. Imaging contrasts of blood-oxygen-level-dependent (BOLD) signal were created by subtracting active control trials from learning and recall trials. A flexible factorial model was employed to investigate the expected group (placebovs. supplement) by time (baselinevs. post-intervention) interaction in pre-specified regions-of-interest.Results:L and Z appeared to buffer cognitive decline on the verbal learning task (Cohen’sd=.84). Significant interactions during learning were observed in left dorsolateral prefrontal cortex and anterior cingulate cortex (p< .05, family-wise-error corrected). However, these effects were in the direction of increased rather than decreased BOLD signal. Although the omnibus interaction was not significant during recall, within-group contrasts revealed significant increases in left prefrontal activation in the supplement group only.Conclusions:L and Z supplementation appears to benefit neurocognitive function by enhancing cerebral perfusion, even if consumed for a discrete period of time in late life. (JINS, 2018,24, 77–90)