Abnormal proactive and reactive cognitive control during conflict processing in major depression

According to the Dual Mechanisms of Control framework, cognitive control consists of two complementary components: proactive control refers to anticipatory maintenance of goal-relevant information, whereas reactive control acts as a correction mechanism that is activated when a conflict occurs. Possibly, the well-known diminished inhibitory control in response to negative stimuli in Major Depressive Disorder (MDD) patients stems from a breakdown in proactive control, and/or anomalies in reactive cognitive control. In our study, MDD patients specifically showed increased response latencies when actively inhibiting a dominant response to a sad compared with a happy face. This condition was associated with a longer duration of a dominant ERP topography (800-900 ms poststimulus onset) and a stronger activity in the bilateral dorsal anterior cingulate cortex, reflecting abnormal reactive control when inhibiting attention to a negative stimulus. Moreover, MDD patients showed abnormalities in proactive cognitive control when preparing for the upcoming imperative stimulus (abnormal modulation of the contingent negative variation component), accompanied by more activity in brain regions belonging to the default mode network. All together, deficits to inhibit attention to negative information in MDD might originate from an abnormal use of both proactive resources and reactive control processes. This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly

Electrical brain imaging reveals the expression and timing of altered error monitoring functions in major depression

Major depressive disorder (MDD) is characterized by disturbances in affect, motivation, and cognitive control processes, including error detection. However, the expression and timing of the impairments during error monitoring remain unclear in MDD. The behavior and event-related brain responses (ERPs) of 20 patients with MDD were compared with those of 20 healthy controls (HCs), while they performed a Go/noGo task. Errors during this task were associated with 2 ERP components, the error-related negativity (ERN/Ne) and the error positivity (Pe). Results show that the ERN/Ne-correct-related negativity (CRN) amplitude difference was significantly larger in MDD patients (after controlling for speed), compared with HCs, although MDD patients exhibited overactive medial frontal cortex (MFC) activation. By comparison, the subsequent Pe component was smaller in MDD patients compared with HCs and this effect was accompanied by a reduced activation of ventral anterior cingulate cortex (ACC) regions. These results suggest that MDD has multiple cascade effects on early error monitoring brain mechanisms

Multisubject Learning for Common Spatial Patterns in Motor-Imagery BCI

Motor-imagery-based brain-computer interfaces (BCIs) commonly use the common spatial pattern filter (CSP) as preprocessing step before feature extraction and classification. The CSP method is a supervised algorithm and therefore needs subject-specific training data for calibration, which is very time consuming to collect. In order to reduce the amount of calibration data that is needed for a new subject, one can apply multitask (from now on called multisubject) machine learning techniques to the preprocessing phase. Here, the goal of multisubject learning is to learn a spatial filter for a new subject based on its own data and that of other subjects. This paper outlines the details of the multitask CSP algorithm and shows results on two data sets. In certain subjects a clear improvement can be seen, especially when the number of training trials is relatively low

Niet willen ingaan op een euthanasievraag is geen teken van onmacht

In het tijdschrift van Similes van maart 2013 hield een psychiater een pleidooi voor euthanasie bij ondraaglijk psychisch lijden. Wij vinden echter dat euthanasie bij psychisch lijden hetzelfde is als assistentie bij suïcide. Dit mag dan ook geen taak zijn van een arts!status: publishe

Niet ingaan op euthanasievraag is geen onmacht

In het tijdschrift van Similes houdt een psychiater een pleidooi voor euthanasie bij ondraaglijk psychisch lijden. Tom Mortier en Georges Otte reageren afwijzend. Euthanasie bij psychisch lijden is hetzelfde als assistentie bij suïcide, schrijven ze. “En dat mag geen taak zijn van een arts.”status: publishe