Prefrontal hypoactivation during working memory in bipolar II depression

Background.Patterns of abnormal neural activation have been observed during working memory tasks in bipolar I depression, yet the neural changes associated with bipolar II depression have yet to be explored.Method.An n-back working memory task was administered during a 3T functional magnetic resonance imaging scan in age- and gender-matched groups of 19 unmedicated, bipolar II depressed subjects and 19 healthy comparison subjects. Whole-brain and region-of-interest analyses were performed to determine regions of differential activation across memory-load conditions (0-, 1- and 2-back).Results.Accuracy for all subjects decreased with higher memory load, but there was no significant group × memory load interaction. Random-effects analyses of memory load indicated that subjects with bipolar II depression exhibited significantly less activation than healthy subjects in left hemispheric regions of the middle frontal gyrus [Brodmann area (BA) 11], superior frontal gyrus (BA 10), inferior parietal lobule (BA 40), middle temporal gyrus (BA 39) and bilateral occipital regions. There was no evidence of differential activation related to increasing memory load in the dorsolateral prefrontal or anterior cingulate cortex.Conclusions.Bipolar II depression is associated with hypoactivation of the left medio-frontal and parietal cortex during working memory performance. Our findings suggest that bipolar II depression is associated with disruption of the fronto-parietal circuit that is engaged in working memory tasks, which is a finding reported across bipolar subtypes and mood states.

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Working memory task induced neural activation: a simultaneous PET/fMRI study

NeuroImage ◽

10.1016/j.neuroimage.2021.118131 ◽

2021 ◽

pp. 118131

Author(s):

Isabelle KD Ripp ◽

Lara A Wallenwein ◽

Qiong Wu ◽

Monica Emch ◽

Kathrin Koch ◽

...

Keyword(s):

Working Memory ◽

Memory Task ◽

Neural Activation ◽

Fmri Study

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Abnormal prefrontal activity subserving attentional control of emotion in remitted depressed patients during a working memory task with emotional distracters

Psychological Medicine ◽

10.1017/s0033291711001097 ◽

2011 ◽

Vol 42 (1) ◽

pp. 29-40 ◽

Cited By ~ 60

Author(s):

R. Kerestes ◽

C. D. Ladouceur ◽

S. Meda ◽

P. J. Nathan ◽

H. P. Blumberg ◽

...

Keyword(s):

Working Memory ◽

Attentional Control ◽

Memory Load ◽

Memory Task ◽

Region Of Interest ◽

Blood Oxygen Level Dependent ◽

Emotional Information ◽

Working Memory Load ◽

Depressed Patients ◽

The Right

BackgroundPatients with major depressive disorder (MDD) show deficits in processing of facial emotions that persist beyond recovery and cessation of treatment. Abnormalities in neural areas supporting attentional control and emotion processing in remitted depressed (rMDD) patients suggests that there may be enduring, trait-like abnormalities in key neural circuits at the interface of cognition and emotion, but this issue has not been studied systematically.MethodNineteen euthymic, medication-free rMDD patients (mean age 33.6 years; mean duration of illness 34 months) and 20 age- and gender-matched healthy controls (HC; mean age 35.8 years) performed the Emotional Face N-Back (EFNBACK) task, a working memory task with emotional distracter stimuli. We used blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to measure neural activity in the dorsolateral (DLPFC) and ventrolateral prefrontal cortex (VLPFC), orbitofrontal cortex (OFC), ventral striatum and amygdala, using a region of interest (ROI) approach in SPM2.ResultsrMDD patients exhibited significantly greater activity relative to HC in the left DLPFC [Brodmann area (BA) 9/46] in response to negative emotional distracters during high working memory load. By contrast, rMDD patients exhibited significantly lower activity in the right DLPFC and left VLPFC compared to HC in response to positive emotional distracters during high working memory load. These effects occurred during accurate task performance.ConclusionsRemitted depressed patients may continue to exhibit attentional biases toward negative emotional information, reflected by greater recruitment of prefrontal regions implicated in attentional control in the context of negative emotional information.

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Occipital Cortex of Blind Individuals Is Functionally Coupled with Executive Control Areas of Frontal Cortex

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00807 ◽

2015 ◽

Vol 27 (8) ◽

pp. 1633-1647 ◽

Cited By ~ 14

Author(s):

Ben Deen ◽

Rebecca Saxe ◽

Marina Bedny

Keyword(s):

Working Memory ◽

Functional Connectivity ◽

Sentence Comprehension ◽

Memory Load ◽

Memory Task ◽

Occipital Cortex ◽

Memory Systems ◽

Functional Responses ◽

Congenitally Blind ◽

Blind Individuals

In congenital blindness, the occipital cortex responds to a range of nonvisual inputs, including tactile, auditory, and linguistic stimuli. Are these changes in functional responses to stimuli accompanied by altered interactions with nonvisual functional networks? To answer this question, we introduce a data-driven method that searches across cortex for functional connectivity differences across groups. Replicating prior work, we find increased fronto-occipital functional connectivity in congenitally blind relative to blindfolded sighted participants. We demonstrate that this heightened connectivity extends over most of occipital cortex but is specific to a subset of regions in the inferior, dorsal, and medial frontal lobe. To assess the functional profile of these frontal areas, we used an n-back working memory task and a sentence comprehension task. We find that, among prefrontal areas with overconnectivity to occipital cortex, one left inferior frontal region responds to language over music. By contrast, the majority of these regions responded to working memory load but not language. These results suggest that in blindness occipital cortex interacts more with working memory systems and raise new questions about the function and mechanism of occipital plasticity.

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Contralateral Delay Activity Tracks Fluctuations in Working Memory Performance

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01233 ◽

2018 ◽

Vol 30 (9) ◽

pp. 1229-1240 ◽

Cited By ~ 32

Author(s):

Kirsten C. S. Adam ◽

Matthew K. Robison ◽

Edward K. Vogel

Keyword(s):

Working Memory ◽

Individual Differences ◽

Memory Load ◽

Memory Performance ◽

Memory Task ◽

Memory Storage ◽

Alpha Power ◽

Working Memory Load ◽

Contralateral Delay Activity ◽

Trial Performance

Neural measures of working memory storage, such as the contralateral delay activity (CDA), are powerful tools in working memory research. CDA amplitude is sensitive to working memory load, reaches an asymptote at known behavioral limits, and predicts individual differences in capacity. An open question, however, is whether neural measures of load also track trial-by-trial fluctuations in performance. Here, we used a whole-report working memory task to test the relationship between CDA amplitude and working memory performance. If working memory failures are due to decision-based errors and retrieval failures, CDA amplitude would not differentiate good and poor performance trials when load is held constant. If failures arise during storage, then CDA amplitude should track both working memory load and trial-by-trial performance. As expected, CDA amplitude tracked load (Experiment 1), reaching an asymptote at three items. In Experiment 2, we tracked fluctuations in trial-by-trial performance. CDA amplitude was larger (more negative) for high-performance trials compared with low-performance trials, suggesting that fluctuations in performance were related to the successful storage of items. During working memory failures, participants oriented their attention to the correct side of the screen (lateralized P1) and maintained covert attention to the correct side during the delay period (lateralized alpha power suppression). Despite the preservation of attentional orienting, we found impairments consistent with an executive attention theory of individual differences in working memory capacity; fluctuations in executive control (indexed by pretrial frontal theta power) may be to blame for storage failures.

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Effects of a secondary task and working memory load on multisensory hand position

Seeing and Perceiving ◽

10.1163/187847612x646794 ◽

2012 ◽

Vol 25 (0) ◽

pp. 58

Author(s):

Katrina Quinn ◽

Francia Acosta-Saltos ◽

Jan W. de Fockert ◽

Charles Spence ◽

Andrew J. Bremner

Keyword(s):

Working Memory ◽

Visual Information ◽

Secondary Task ◽

Memory Load ◽

Memory Task ◽

Hand Position ◽

Working Memory Load ◽

The Individual ◽

Task Conditions ◽

Relative Weighting

Information about where our hands are arises from different sensory modalities; chiefly proprioception and vision. These inputs differ in variability from situation to situation (or task to task). According to the idea of ‘optimal integration’, the information provided by different sources is combined in proportion to their relative reliabilities, thus maximizing the reliability of the combined estimate. It is uncertain whether optimal multisensory integration of multisensory contributions to limb position requires executive resources. If so, then it should be possible to observe effects of secondary task performance and/or working memory load (WML) on the relative weighting of the senses under conditions of crossmodal sensory conflict. Alternatively, an integrated signal may be affected by upstream influences of WML or a secondary task on the reliabilities of the individual sensory inputs. We examine these possibilities in two experiments which examine effects of WML on reaching tasks in which bisensory visual-proprioceptive (Exp. 1), and unisensory proprioceptive (Exp. 2) cues to hand position are provided. WML increased visual capture under conditions of visual-proprioceptive conflict, regardless of the direction of visual-proprioceptive conflict, and the degree of load imposed. This indicates that task-switching (rather than WML load) leads to an increased reliance on visual information regardless of its task-specific reliability (Exp. 1). This could not be explained due to an increase in the variability of proprioception under secondary working memory task conditions (Exp. 2). We conclude that executive resources are involved in the relative weighting of visual and proprioceptive cues to hand position.

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Working Memory and the Suppression of Reflexive Saccades

Journal of Cognitive Neuroscience ◽

10.1162/089892902317205357 ◽

2002 ◽

Vol 14 (1) ◽

pp. 95-103 ◽

Cited By ~ 80

Author(s):

Jason P. Mitchell ◽

C. Neil Macrae ◽

Iain D. Gilchrist

Keyword(s):

Working Memory ◽

Memory Load ◽

Critical Role ◽

Memory Task ◽

Behavioral Responses ◽

Error Rates ◽

Antisaccade Task ◽

Working Memory Load ◽

Reflexive Saccades ◽

Back Task

Conscious behavioral intentions can frequently fail under conditions of attentional depletion. In attempting to trace the cognitive origin of this effect, we hypothesized that failures of action control—specifically, oculomotor movement—can result from the imposition of fronto-executive load. To evaluate this prediction, participants performed an antisaccade task while simultaneously completing a working-memory task that is known to make variable demands on prefrontal processes (n-back task, see Jonides et al., 1997). The results of two experiments are reported. As expected, antisaccade error rates were increased in accordance with the fronto-executive demands of the n-back task (Experiment 1). In addition, the debilitating effects of working-memory load were restricted to the inhibitory component of the antisaccade task (Experiment 2). These findings corroborate the view that working memory operations play a critical role in the suppression of prepotent behavioral responses.

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Cognitive Performance, Aerobic Fitness, Motor Proficiency, and Brain Function Among Children Newly Diagnosed With Craniopharyngioma

Journal of the International Neuropsychological Society ◽

10.1017/s1355617718001170 ◽

2019 ◽

Vol 25 (04) ◽

pp. 413-425 ◽

Cited By ~ 1

Author(s):

Heather M. Conklin ◽

Kirsten K. Ness ◽

Jason M. Ashford ◽

Matthew A. Scoggins ◽

Robert J. Ogg ◽

...

Keyword(s):

Working Memory ◽

Executive Functions ◽

Aerobic Fitness ◽

Memory Task ◽

Peak Oxygen Uptake ◽

Neural Activation ◽

Proton Radiation ◽

Cognitive Changes ◽

Motor Proficiency ◽

Network Activation

AbstractObjectives: Craniopharyngioma survivors experience cognitive deficits that negatively impact quality of life. Aerobic fitness is associated with cognitive benefits in typically developing children and physical exercise promotes recovery following brain injury. Accordingly, we investigated cognitive and neural correlates of aerobic fitness in a sample of craniopharyngioma patients. Methods: Patients treated for craniopharyngioma [N=104, 10.0±4.6 years, 48% male] participated in fitness, cognitive and fMRI (n=51) assessments following surgery but before proton radiation therapy. Results: Patients demonstrated impaired aerobic fitness [peak oxygen uptake (PKVO2)=23.9±7.1, 41% impaired (i.e., 1.5 SD<normative mean)], motor proficiency [Bruininks-Oseretsky (BOT2)=38.6±9.0, 28% impaired], and executive functions (e.g., WISC-IV Working Memory Index (WMI)=96.0±15.3, 11% impaired). PKVO2 correlated with better executive functions (e.g., WISC-IV WMI r=.27, p=.02) and academic performance (WJ-III Calculation r=.24, p=.04). BOT2 correlated with better attention (e.g., CPT-II omissions r=.26, p=.04) and executive functions (e.g., WISC-IV WMI r=.32, p=.01). Areas of robust neural activation during an n-back task included superior parietal lobule, dorsolateral prefrontal cortex, and middle and superior frontal gyri (p<.05, corrected). Higher network activation was associated with better working memory task performance and better BOT2 (p<.001). Conclusions: Before adjuvant therapy, children with craniopharyngioma demonstrate significantly reduced aerobic fitness, motor proficiency, and working memory. Better aerobic fitness and motor proficiency are associated with better attention and executive functions, as well as greater activation of a well-established working memory network. These findings may help explain differential risk/resiliency with respect to acute cognitive changes that may portend cognitive late effects. (JINS, 2019, 25, 413–425)

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Learning to suppress a distractor is not affected by working memory load

Psychonomic Bulletin & Review ◽

10.3758/s13423-019-01679-6 ◽

2019 ◽

Vol 27 (1) ◽

pp. 96-104 ◽

Cited By ~ 3

Author(s):

Ya Gao ◽

Jan Theeuwes

Keyword(s):

Working Memory ◽

High Probability ◽

Spatial Working Memory ◽

Memory Load ◽

Working Memory Capacity ◽

Memory Task ◽

Automatic Process ◽

Long Term Memory ◽

Working Memory Load ◽

Statistical Regularities

AbstractWhere and what we attend to is not only determined by our current goals but also by what we have encountered in the past. Recent studies have shown that people learn to extract statistical regularities in the environment resulting in attentional suppression of high-probability distractor locations, effectively reducing capture by a distractor. Here, we asked whether this statistical learning is dependent on working memory resources. The additional singleton task in which one location was more likely to contain a distractor was combined with a concurrent visual working memory task (Experiment 1) and a spatial working memory task (Experiment 2). The result showed that learning to suppress this high-probability location was not at all affected by working memory load. We conclude that learning to suppress a location is an implicit and automatic process that does not rely on visual or spatial working memory capacity, nor on executive control resources. We speculate that extracting regularities from the environment likely relies on long-term memory processes.

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Performance Dissociation during Verbal and Spatial Working Memory Tasks

Perceptual and Motor Skills ◽

10.2466/pms.105.1.243-250 ◽

2007 ◽

Vol 105 (1) ◽

pp. 243-250 ◽

Cited By ~ 12

Author(s):

Bonnie J. Nagel ◽

Arthur Ohannessian ◽

Kevin Cummins

Keyword(s):

Working Memory ◽

Spatial Working Memory ◽

Memory Load ◽

Memory Task ◽

Past Research ◽

Neural Substrates ◽

Individual Performance ◽

Task Design ◽

Brain Response ◽

Working Memory Load

Past research has inconsistently distinguished the neural substrates of various types of working memory. Task design and individual performance differences are known to alter patterns of brain response during working-memory tasks. These task and individual differences may have produced discrepancies in imaging findings. This study of 50 healthy adults ( Mage = 19.6 yr., SD = .8) examined performance during various parametric manipulations of a verbal and spatial n-back working-memory task. Performance systematically dissociated on the basis of working-memory load, working memory type, and stimulus difficulty, with participants having greater accuracy but slower response time during conditions requiring verbal versus spatial working memory. These findings hold implications for cognitive and neuroimaging studies of verbal and spatial working memory and highlight the importance of considering both task design and individual behavior.

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Neural correlates of executive function and working memory in the ‘at-risk mental state’

The British Journal of Psychiatry ◽

10.1192/bjp.bp.107.046789 ◽

2009 ◽

Vol 194 (1) ◽

pp. 25-33 ◽

Cited By ~ 101

Author(s):

Matthew R. Broome ◽

Pall Matthiasson ◽

Paolo Fusar-Poli ◽

James B. Woolley ◽

Louise C. Johns ◽

...

Keyword(s):

At Risk ◽

Working Memory ◽

Mental State ◽

Verbal Fluency ◽

Risk Group ◽

Memory Task ◽

Anterior Cingulate ◽

Verbal Fluency Task ◽

Fluency Task ◽

At Risk Mental State

BackgroundPeople with prodromal symptoms have a very high risk of developing psychosis.AimsTo use functional magnetic resonance imaging to examine the neurocognitive basis of this vulnerability.MethodCross-sectional comparison of regional activation in individuals with an ‘at-risk mental state’ (at-risk group: n=17), patients with first-episode schizophreniform psychosis (psychosis group: n=10) and healthy volunteers (controls: n=15) during an overt verbal fluency task and an N-back working memory task.ResultsA similar pattern of between-group differences in activation was evident across both tasks. Activation in the at-risk group was intermediate relative to that in controls and the psychosis group in the inferior frontal and anterior cingulate cortex during the verbal fluency task and in the inferior frontal, dorsolateral prefrontal and parietal cortex during the N-back task.ConclusionsThe at-risk mental state is associated with abnormalities of regional brain function that are qualitatively similar to, but less severe than, those in patients who have recently presented with psychosis.

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