The Effects of Guanfacine on Working Memory Performance in Patients With Localization-Related Epilepsy and Healthy Controls

BackgroundPrevious studies have suggested that motivational aspects of executive functioning, which may be disrupted in schizophrenia patients with negative symptoms, are mediated in part by the striatum. Negative symptoms have been linked to impaired recruitment of both the striatum and the dorsolateral prefrontal cortex (DLPFC). Here we tested the hypothesis that negative symptoms are associated primarily with striatal dysfunction, using functional magnetic resonance imaging (fMRI).MethodWorking-memory load-dependent activation and gray matter volumes of the striatum and DLPFC were measured using a region-of-interest (ROI) approach, in 147 schizophrenia patients and 160 healthy controls. In addition to testing for a linear relationships between striatal function and negative symptoms, we chose a second, categorical analytic strategy in which we compared three demographically and behaviorally matched subgroups: patients with a high burden of negative symptoms, patients with minimal negative symptoms, and healthy subjects.ResultsThere were no differences in striatal response magnitudes between schizophrenia patients and healthy controls, but right DLPFC activity was higher in patients than in controls. Negative symptoms were inversely associated with striatal, but not DLPFC, activity. In addition, patients with a high burden of negative symptoms exhibited significantly lower bilateral striatal, but not DLPFC, activation than schizophrenia patients with minimal negative symptoms. Working memory performance, antipsychotic exposure and changes in gray matter volumes did not account for these differences.ConclusionsThese data provide further evidence for a robust association between negative symptoms and diminished striatal activity. Future work will determine whether low striatal activity in schizophrenia patients could serve as a reliable biomarker for negative symptoms.

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Spatial working memory performance in people with obsessive–compulsive disorder, their unaffected first-degree relatives and healthy controls

BJPsych Open ◽

10.1192/bjo.2021.1052 ◽

2021 ◽

Vol 7 (6) ◽

Author(s):

Stephan Heinzel ◽

Katharina Bey ◽

Rosa Grützmann ◽

Julia Klawohn ◽

Christian Kaufmann ◽

...

Keyword(s):

Working Memory ◽

Obsessive Compulsive Disorder ◽

Spatial Working Memory ◽

Memory Performance ◽

Age Effects ◽

Healthy Controls ◽

Obsessive Compulsive ◽

Compulsive Disorder ◽

First Degree Relatives ◽

Healthy Control

Summary Studies have shown that people with obsessive–compulsive disorder (OCD) have impairments in spatial working memory (SWM) performance. However, it remains unclear whether this deficit represents a cognitive endophenotype preceding symptoms or a correlate of OCD. We investigated SWM in 69 people with OCD, 77 unaffected first-degree relatives of people with OCD and 106 healthy control participants. Taking age effects into account, SWM performance was best in healthy controls, intermediate in relatives and worst in OCD participants. However, since performance did not differ significantly between healthy controls and relatives, our study does not fully support SWM performance as a core cognitive endophenotype of OCD.

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Behavioural and neurophysiological differences in working memory function of depressed patients and healthy controls

10.31234/osf.io/h8dmr ◽

2020 ◽

Author(s):

Stevan Nikolin ◽

Yi Yin Tan ◽

Donel Martin ◽

Adriano Moffa ◽

Colleen Loo ◽

...

Keyword(s):

Working Memory ◽

Response Times ◽

Memory Performance ◽

Memory Function ◽

Memory Task ◽

Cognitive Resources ◽

Healthy Controls ◽

Psychomotor Slowing ◽

Functional Deficits ◽

And Gender

Objective: Major depressive disorder (MDD) is associated with deficits in working memory. Several cognitive subprocesses interact to produce working memory, including attention, encoding, maintenenace and manipulation. We sought to clarify the contribution of functional deficits in these subprocesses in MDD by varying cognitive load during a working memory task.Methods: 41 depressed participants and 41 age- and gender-matched healthy controls performed the n-back working memory task at three levels of difficulty (0-, 1-, and 2-back) in a pregistered study. We assessed response times, accuracy, and event-related electroencephalography (EEG), including P2 and P3 amplitudes, and frontal theta power (4-8 Hz). Results: MDD participants had prolonged response times and more positive P3 amplitudes relative to controls. Working memory accuracy, P2 amplitudes and frontal theta event-related synchronisation did not differ between groups at any level of task difficulty.Conclusions: Depression is associated with generalized psychomotor slowing of working memory processes, as well as compensatory hyperactivity in frontal regions.Significance: These findings provide insights into MDD working memory deficits, indicating that depressed individuals dedicate greater levels of cortical processing and cognitive resources to achieve comparable workig memory performance to controls.

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Emotional reagibility and working memory performance - differential effects of emotional interference control in subjects with and without ADHD

European Psychiatry ◽

10.1016/s0924-9338(11)72912-1 ◽

2011 ◽

Vol 26 (S2) ◽

pp. 1207-1207

Author(s):

I. Marx ◽

G. Domes ◽

C. Havenstein ◽

C. Berger ◽

L. Schulze ◽

...

Keyword(s):

Working Memory ◽

Emotion Regulation ◽

Memory Performance ◽

Reaction Times ◽

Healthy Controls ◽

Interference Control ◽

Monitoring And Control ◽

Differential Effects ◽

Performance Accuracy ◽

Display Performance

In a number of studies, it has been shown that subjects with attention-deficit/hyperactivity disorder (ADHD) show deficits in executive functioning, i.e. in cognitive functions that subserve planning, monitoring and control of goal-directed behaviour (Martinussen et al., 2005; Willcutt et al., 2005), as well as in emotion regulation (Berlin et al., 2004; Desman et al., 2006). However, no study exists so far examining the interaction between cognition and emotion regulation in subjects with ADHD. In our study, we aimed to examine to what extend arousing emotional picture stimuli may account for differential effects in performance quality in subjects with and without ADHD. Thirty-nine males and females with ADHD aged 18 to 40 years and 40 matched healthy controls performed a working memory n-back task (1-back, 2-back). The task was performed with and without neutral and negative background pictures from the International Affective Picture System (IAPS) which varied in arousal (low, medium, high). Irrespective of ADHD diagnosis, all subjects were slower and demonstrated lower performance accuracy in the 2-back condition compared with the 1-back condition, and all subjects deteriorated with increasing picture arousal. In comparison to healthy controls, subjects with ADHD displayed a deficit in working memory performance in terms of prolonged reaction times and decreased performance accuracy. Beyond this, we found that whereas healthy controls did not display performance deficits until they were presented with high-arousal background pictures, subjects with ADHD were already impaired when presented with medium-arousal background pictures. The implications of these and further findings will be discussed.

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