Max Owens

Improving attention control in dysphoria through cognitive training: transfer effects on working memory capacity and filtering efficiency.

Impaired filtering of irrelevant information from working memory is thought to underlie reduced working memory capacity for relevant information in dysphoria. The current study investigated whether training-related gains in working memory performance on the adaptive dual n-back task could result in improved inhibitory function. Efficacy of training was monitored in a change detection paradigm allowing measurement of a sustained event-related potential asymmetry sensitive to working memory capacity and the efficient filtering of irrelevant information. Dysphoric participants in the training group showed training-related gains in working memory that were accompanied by gains in working memory capacity and filtering efficiency compared to an active control group. Results provide important initial evidence that behavioral performance and neural function in dysphoria can be improved by facilitating greater attentional control.

Developmental changes in spontaneous electrocortical activity and network organization from early to late childhood

We investigated the development of spontaneous (resting state) cerebral electric fields and their network organization from early to late childhood in a large community sample of children. Critically, we examined electrocortical maturation across one-year windows rather than creating aggregate averages that can miss subtle maturational trends. We implemented several novel methodological approaches including a more fine grained examination of spectral features across multiple electrodes, the use of phase-lagged functional connectivity to control for the confounding effects of volume conduction and applying topological network analyses to weighted cortical adjacency matrices. Overall, there were major decreases in absolute EEG spectral density (particularly in the slow wave range) across cortical lobes as a function of age. Moreover, the peak of the alpha frequency increased with chronological age and there was a redistribution of relative spectral density toward the higher frequency ranges, consistent with much of the previous literature. There were age differences in long range functional brain connectivity, particularly in the alpha frequency band, culminating in the most dense and spatially variable networks in the oldest children. We discovered age-related reductions in characteristic path lengths, modularity and homogeneity of alpha-band cortical networks from early to late childhood. In summary, there is evidence of large scale reorganization in endogenous brain electric fields from early to late childhood, suggesting reduced signal amplitudes in the presence of more functionally integrated and band limited coordination of neuronal activity across the cerebral cortex.

Cognitive control interventions for depression: A systematic review of findings from training studies

There is a strong interest in cognitive control training as a new intervention for depression. Given the recent promising meta-analytical findings regarding the effects of cognitive training on cognitive functioning and depressive symptomatology, the current review provides an in-depth discussion of the role of cognitive control in depression. We consider the state-of-the-art research on how manipulation of cognitive control may influence cognitive and depression-related outcomes. Evidence for the effectiveness of cognitive control training procedures are discussed in relation to three stages of depression (at-risk, clinically depressed, remission) as well as the training approach that was deployed, after which the putative theoretical mechanisms are discussed. Finally, we provide ways in which cognitive control training can be utilized in future research.

The effects of dysphoria and rumination on cognitive flexibility and task selection

Executive dysfunction in dysphoria and dysphoric rumination is often reflected as a difficulty to alter behaviour in response to task demands and is associated with performance deficits on measures of cognitive flexibility. In the present study, participants were required to switch between two randomly ordered spatial location tasks in which the position of a target within a 2×2 grid was determined according to a horizontal or vertical dimension. The typical congruency effect in task switching was replicated such that interference from a currently irrelevant task was associated with slower and inaccurate responses for a currently relevant task. High-ruminators, compared with low-ruminators, displayed poor filtering of the currently irrelevant task which in turn resulted in a specific task selection deficit, and a tendency to perform the irrelevant task. Results suggest that an impaired ability in selecting the appropriate task promoted application of the most salient task regardless of relevance. Our findings extend previous research linking impaired inhibition of irrelevant information with cognitive inflexibility in dysphoric rumination, and argue for an independent contribution of dysphoric rumination to cognitive deficits observed in dysphoria.

Eye tracking indices of attentional bias in children of depressed mothers: Polygenic influences help to clarify previous mixed findings

Information-processing biases may contribute to the intergenerational transmission of depression. There is growing evidence that children of depressed mothers exhibit attentional biases for sad faces. However, findings are mixed as to whether this bias reflects preferential attention toward, versus attentional avoidance of, sad faces, suggesting the presence of unmeasured moderators. To address these mixed findings, we focused on the potential moderating role of genes associated with hypothalamic-pituitary-adrenal axis reactivity. Participants included children (8-14 years old) of mothers with (n = 81) and without (n = 81) a history of depression. Eye movements were recorded while children passively viewed arrays of angry, happy, sad, and neutral faces. DNA was obtained from buccal cells. Children of depressed mothers exhibited more sustained attention to sad faces than did children of nondepressed mothers. However, it is important that this relation was moderated by childrens genotype. Specifically, children of depressed mothers who carried reactive genotypes across the corticotropin-releasing hormone type 1 receptor (CHRH1) TAT haplotype and FK506 binding protein 5 (FKBP5) rs1360780 (but not the solute carrier family C6 member 4 [SLC6A4] of the serotonin transporter linked polymorphic region [5-HTTLPR]) exhibited less sustained attention to sad faces and more sustained attention to happy faces. These findings highlight the role played by specific genetic influences and suggest that previous mixed findings may have been due to genetic heterogeneity across the samples.

Sensitivity in detecting facial displays of emotion: Impact of maternal depression and oxytocin receptor genotype

The current study examined sensitivity in detecting emotional faces among children of depressed and non-depressed mothers. A second goal was to examine the potential moderating role of the oxytocin receptor gene (OXTR rs53576), which has been linked to emotion recognition in the past. Participants included 247 children (ages 8–14). Children completed a forced choice emotion identification task. Maternal history of major depressive disorder during childrens lives was associated with childrens sensitivity in detecting emotional faces among children homozygous for the OXTR rs53576 G allele, but not among carriers of the A allele. Among G homozygotes, children of depressed mothers exhibited increased sensitivity in detecting sad faces, and reduced sensitivity in detecting happiness, compared to children of non-depressed mothers.

Charting moment-to-moment brain signal variability from early to late childhood

Large-scale brain signals exhibit rich intermittent patterning, reflecting the fact that the cortex actively eschews fixed points in favor of itinerant wandering with frequent state transitions. Fluctuations in endogenous cortical activity occur at multiple time scales and index a dynamic repertoire of network states that are continuously explored, even in the absence of external sensory inputs. Here, we quantified such moment-to-moment brain signal variability at rest in a large, cross-sectional sample of children ranging in age from seven to eleven years. Our findings revealed a monotonic rise in the complexity of electroencephalogram (EEG) signals as measured by sample entropy, from the youngest to the oldest age cohort, across a range of time scales and spatial regions. From year to year, the greatest changes in intraindividual brain signal variability were recorded at electrodes covering the anterior cortical zones. These results provide converging evidence concerning the age-dependent expansion of functional cortical network states during a critical developmental period ranging from early to late childhood.

Brooding rumination and attentional biases in currently non-depressed individuals: an eye-tracking study

ABSTRACT Both rumination and attentional biases have been proposed as key components of the RDoC Negative Valence Systems construct of Loss. Although theorists have proposed that rumination, particularly brooding rumination, should be associated with increased sustained attention to depression-relevant information, it is not clear whether this link would be observed in a non-depressed sample or whether it is specific to brooding versus reflective rumination. To address these questions, the current study examined the link between brooding rumination and attentional biases in a sample of non-depressed individuals (n = 105). Attentional biases were assessed using eye tracking during a passive viewing task in which participants were presented with 2 × 2 arrays of angry, happy, sad, and neutral faces. In line with predictions, higher levels of brooding rumination were associated with greater sustained attention to sad faces and less sustained attention to happy faces. These results remained significant after controlling for participants’ prior history of major depression and current nonclinical level of depressive symptoms, suggesting that the link between brooding rumination and attentional biases is at least partially independent of current or past depression.

Differences in emotion modulation using cognitive reappraisal in individuals with and without suicidal ideation: An ERP study

Difficulties in emotion regulation have been associated with increased suicidal thoughts and behaviours. The majority of studies have examined self-reported use of emotion regulation strategies. In contrast, the current study focused on a direct measure of individuals’ ability to use a specific emotion regulation strategy, cognitive reappraisal, using the late positive potential (LPP), an event-related potential component that reflects attention to emotional stimuli. Specifically, the cognitive reappraisal ability of 33 undergraduate students was assessed via an image-viewing task during which the participants had to passively view, increase or reduce their emotions in response to looking at neutral, positive or dysphoric images. We found that participants with a history of suicidal ideation (SI) had significantly higher LPP when asked to reduce negative emotion in response to dysphoric images, compared to individuals with no history of SI. These findings suggest that difficulties with using cognitive reappraisal, specifically to decrease negative affect, might be linked to suicide risk.

Distinct functional and structural neural underpinnings of working memory

ABSTRACT Working memory (WM), the short‐term abstraction and manipulation of information, is an essential neurocognitive process in daily functioning. Few studies have concurrently examined the functional and structural neural correlates of WM and the current study did so to characterize both overlapping and unique associations. Participants were a large sample of adults from the Human Connectome Project (N=1064; 54% female) who completed an in‐scanner visual N‐back WM task. The results indicate a clear dissociation between BOLD activation during the WM task and brain structure in relation to performance. In particular, while activation in the middle frontal gyrus was positively associated with WM performance, cortical thickness in this region was inversely associated with performance. Additional unique associations with WM were BOLD activation in superior parietal lobule, cingulate, and fusiform gyrus and gray matter volume in the orbitofrontal cortex and cuneus. Across findings, substantially larger effects were observed for functional associations relative to structural associations. These results provide further evidence implicating frontoparietal subunits of the brain in WM. Moreover, these findings reveal the distinct, and in some cases opposing, roles of brain structure and neural activation in WM, highlighting the lack of homology between structure and function in relation to cognition. HIGHLIGHTSInvestigation of the functional and structural neural correlates of working memory.Measured by a visual N‐Back task in a large adult sample (N=1064).Larger associations for BOLD signal relative to morphometry.Lack of homology between structure and function in relation to cognition.Dissociation especially notable for middle frontal gyrus.