The effect of induced sadness and moderate depression on attention networks

Disruptions in self-regulatory processes predict depression and sleep disturbance in bereaved young adults

Losing a loved one is both common and profoundly stressful for young adults. Little research has examined the longitudinal course of post-loss cognitive processing, depression, and sleep difficulties. Further, little is known about the context of other stressors or the role of individual regulatory resources, such as attentional regulation, that might determine whether loss-related cognitive processing reduces distress. This prospective study examined changes in depression and sleep disturbance over 9 weeks as a function of within- and between-person variation in stress exposure, loss-related cognitive processing, and attention regulation. Participants were 108 recently bereaved college students completing a lab-based assessment of attention regulation and four self-report surveys, spaced three weeks apart. Results revealed that most participants gradually reduced loss-related processing over the study period, with corresponding improvements in depression and sleep. Stress exposure was associated with increased processing, depression, and sleep disturbance. In exploratory analyses, high attentional alertness and slow re-orienting strengthened the association of within-person loss processing with sleep disturbance. Both within- and between-person variation in stress appear to engender risk for a prolonged course of bereavement. Future research should integrate objective attention measures with self-reported adjustment to stress to illuminate reciprocal links between depression, sleep, and loss-related cognitive processing.

Measuring the attention networks and quantitative-electroencephalography correlates of attention in depression

Given the association between major depressive disorder (MDD) and cortical inefficiency related to executive control, specifically in the sense that individuals with MDD may recruit more cognitive resources to complete tasks at the same capacity as those without MDD, the current study was interested in examining the attention networks and executive functioning of those with MDD. Past research has used the Attention Network Test (ANT) to measure changes of attention in clinical vs. healthy populations; however, theoretical concerns have been raised regarding the task. The Combined Attention Systems Task (CAST) was developed to address these concerns and was used in our study in combination with quantitative-electroencephalography (QEEG) to assess both behavioural and neurophysiological changes in participants with MDD (n = 18) compared to healthy controls (HCs; n = 22). We found no behavioural differences between MDD and HC groups suggesting individuals with MDD in our sample were not experiencing the executive functioning deficits previously reported in the literature. Neurophysiological measures of attention revealed that MDD participants had greater theta and alpha₁ activity relative to HCs, suggesting that although individuals with MDD do not show deficits in behavioural attention, they exhibit altered neural processing which underlies cognitive function.

Neutral and negative mood induction in executive tasks of working memory

The mood induction paradigm has been an important tool for investigating the effects of negative emotional states on working memory (WM) executive functions. Though some evidence showed that negative mood has a differential effect on verbal and visuospatial WM, other findings did not report a similar effect. To explore this issue, we examined the negative mood's impact on verbal and visuospatial WM executive tasks based on grammatical reasoning and visuospatial rotation. Participants with no anxiety or depression disorders performed the tasks before and after negative (n = 14) or neutral (n = 13) mood induction. Participants' mood at the beginning and the end of the session was assessed by the Present Mood States List (LEAP) and word valence rating. The analyses showed changes in the emotional state of the negative group (ps < .03) but not of the neutral group (ps > .83) in the LEAP instrument. No significant differences between groups were observed in the WM tasks (ps > .33). Performance in the visuospatial WM task improved after mood induction for both groups (p < .05), possibly due to a practice effect. In sum, our findings challenge the view that negative mood modulates WM executive functions; thus, they were discussed considering the similarities and differences between studies that found negative mood effects on WM and those that did not find. Different WM tasks tap distinct processes and components, which may underlie behavioral effects of negative mood on WM tasks.

Functional plasticity abnormalities over the lifespan of first-episode patients with major depressive disorder: a resting state fMRI study

Background

Neurodevelopmental and neurodegenerative theories of depression suggest that patients with major depressive disorder (MDD) may follow abnormal developmental, maturational, and aging processes. However, a lack of lifespan studies has precluded verification of these theories. Herein, we analyzed functional magnetic resonance imaging (fMRI) data to comprehensively characterize age-related functional trajectories, as measured by the fractional amplitude of low frequency fluctuations (fALFF), over the course of MDD.

Methods

In total, 235 MDD patients with age-differentiated onsets and 235 age- and sex-matched healthy controls (HC) were included in this study. We determined the pattern of age-related fALFF changes by cross-sectionally establishing the general linear model (GLM) between fALFF and age over a lifespan. Furthermore, the subjects were divided into four age groups to assess age-related neural changes in detail. Inter-group fALFF comparison (MDD vs. HC) was conducted in each age group and Granger causal analysis (GCA) was applied to investigate effective connectivity between regions.

Results

Compared with the HC, no significant quadratic or linear age effects were found in MDD over the entire lifespan, suggesting that depression affects the normal developmental, maturational, and degenerative process. Inter-group differences in fALFF values varied significantly at different ages of onset. This implies that MDD may impact brain functions in a highly dynamic way, with different patterns of alterations at different stages of life. Moreover, the GCA analysis results indicated that MDD followed a distinct pattern of effective connectivity relative to HC, and this may be the neural basis of MDD with age-differentiated onsets.

Conclusions

Our findings provide evidence that normal developmental, maturational, and ageing processes were affected by MDD. Most strikingly, functional plasticity changes in MDD with different ages of onset involved dynamic interactions between neuropathological processes in a tract-specific manner.

Age-Related Diseases and Driving Safety

Due to demographic changes, the number of older drivers is steadily increasing. Mobility is highly relevant for leading an independent life in the elderly. It largely depends on car driving, which is a complex task requiring a multitude of cognitive and motor skills vulnerable to age- related functional deterioration. The almost inevitable effects of senescence may be potentiated by age-related diseases, such as stroke or diabetes mellitus. Respective pharmacological treatment may cause side effects, additionally affecting driving safety. The present article reviews the impact of age-related diseases and drug treatment of these conditions on driving fitness in elderly drivers. In essence, we focus on diseases of the visual and auditory systems, diseases of the central nervous system (i.e., stroke, depression, dementia and mild cognitive disorder, and Parkinson's disease), sleep disorders, as well as cardiovascular diseases, diabetes mellitus, musculoskeletal disorders, and frailty. We will outline the role of functional tests and the assessment of driving behavior (by a driving simulator or in real traffic), as well as the clinical interview including questions about frequency of (near) accidents, etc. in the evaluation of driving fitness of the elderly. We also address the impact of polypharmacy on driving fitness and end up with recommendations for physicians caring for older patients.

Looming fear stimuli broadens attention in a local-global letter task

This chapter provides an overview of the literature on emotion and global/local processing and presents an empirical study exploring how the combination of motion and emotion influences the focus of attention. In two experiments, fear-related pictures either loomed toward the observer or were stationary, and in one of these experiments the emotional content was masked (i.e., scrambled pictures). In the context of fearful pictures, it was expected that the additional element of looming motion would further focus attention based on looming motion's behaviorally urgent properties. However, the combination of a fearful image and looming motion was shown to broaden as opposed to narrow attention. This effect did not occur with simply neutral/looming or fearful/static images. Further, the separation of the emotional content from looming motion (scrambled pictures) revealed no effect on attentional breadth. This suggests that it is the unique combination of the fear-related content and the looming motion, which is broadening attention.

Executive control dysfunction in subclinical depressive undergraduates: Evidence from the Attention Network Test

BACKGROUND

It has been proposed that depressed individuals have broad neuropsychological dysfunction, particularly in the executive control domain. The Attention Network Test (ANT) is widely used to assess the efficiency of three attention networks: alerting, orienting, and executive control. In the present study, we investigated the behavioral and event-related potential (ERP) indicators of attention processing in subclinical depressive undergraduates.

METHODS

Seventeen undergraduates with subclinical depressive symptoms and sixteen control undergraduates completed the Attention Network Test (ANT).

RESULTS

The results indicated no difference in behavioral performance on the three attention networks between the two groups; and there was a similar ERP pattern in the ERP components involved in alerting and orienting (cue-N1 and target-N1) in both groups. Additionally, for executive function network, no difference in the N2 component associated with conflict detection was observed between the two groups. However, there was an increase in the congruency effect of the conflict-sustained potential (SP; incongruent minus congruent) related to conflict resolution in undergraduates with subclinical depressive symptoms compared with control undergraduates.

LIMITATIONS

The present study is limited by its small sample size which might result in inadequate statistical power to detect potential group differences in behavior. Additionally, the present study focused primarily on individuals with subclinical depression, and the extent to which these findings would generalize to those with more severe symptoms or clinical major depressive disorder is unknown.

CONCLUSIONS

The findings suggest that undergraduates with subclinical depressive symptoms might need to recruit additional compensatory cognitive resources to obtain an equivalent behavioral performance compared with that in undergraduates with none or few depressive symptoms in executive control processing. The current study further provides evidence for the cortical inefficiency theory, which might account for executive control dysfunction in individuals with subclinical depression.

The Effects of Low and High Levels of Sadness on Scope of Attention: An ERP Study

Sadness has inconsistent effects on the scope of attention. These differing effects may be attributed to different levels of sadness induced in different experiments. Low levels of sadness can expand the scope of attention, but high levels can narrow it. In this study, we recruited 42 college students and induced different levels of sadness in them by having them view sad images continuously, and then we assigned them Navon's letter task. The results showed that among participants with local-processing bias, those at lower levels of sadness were slower to identify small letters than were those at high levels of sadness and control condition (watching neutral images). Event-related potential (ERP) results showed that low-sadness participants put more attention resources toward processing large letters (global stimuli). They showed increased amplitude of the P1 component compared with high-sadness participants and participants at control condition. These results suggested that different levels of sadness had different effects on attention scope: low levels of sadness extended the scope but as sadness increased, this extension disappeared. This influence pattern mainly occurred in the early stages of visual processing.