Tracking the Contents of Spatial Working Memory during an Acute Bout of Aerobic Exercise

Abstract Recent studies have reported enhanced visual responses during acute bouts of physical exercise, suggesting that sensory systems may become more sensitive during active exploration of the environment. This raises the possibility that exercise may also modulate brain activity associated with other cognitive functions, like visual working memory, that rely on patterns of activity that persist beyond the initial sensory evoked response. Here, we investigated whether the neural coding of an object location held in memory is modulated by an acute bout of aerobic exercise. Participants performed a spatial change detection task while seated on a stationary bike at rest and during low-intensity cycling (∼50 watts/50 RPM). Brain activity was measured with EEG. An inverted encoding modeling technique was employed to estimate location-selective channel response functions from topographical patterns of alpha-band (8–12 Hz) activity. There was strong evidence of robust spatially selective responses during stimulus presentation and retention periods both at rest and during exercise. During retention, the spatial selectivity of these responses decreased in the exercise condition relative to rest. A temporal generalization analysis indicated that models trained on one time period could be used to reconstruct the remembered locations at other time periods, providing evidence that a unitary code supports memory during both conditions. However, generalization was degraded during exercise. Together, these results demonstrate that it is possible to reconstruct the contents of working memory at rest and during exercise, but that exercise can result in degraded responses, which contrasts with the enhancements observed in early sensory processing.

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Resting‐State EEG Microstates Parallel Age‐Related Differences in Allocentric Spatial Working Memory Performance

Brain Topography ◽

10.1007/s10548-021-00835-3 ◽

2021 ◽

Author(s):

Adeline Jabès ◽

Giuliana Klencklen ◽

Paolo Ruggeri ◽

Christoph M. Michel ◽

Pamela Banta Lavenex ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Resting State ◽

Cognitive Aging ◽

Temporal Dynamics ◽

Spatial Working Memory ◽

Brain Activity ◽

Memory Performance ◽

Brain Regions ◽

Age Related

AbstractAlterations of resting-state EEG microstates have been associated with various neurological disorders and behavioral states. Interestingly, age-related differences in EEG microstate organization have also been reported, and it has been suggested that resting-state EEG activity may predict cognitive capacities in healthy individuals across the lifespan. In this exploratory study, we performed a microstate analysis of resting-state brain activity and tested allocentric spatial working memory performance in healthy adult individuals: twenty 25–30-year-olds and twenty-five 64–75-year-olds. We found a lower spatial working memory performance in older adults, as well as age-related differences in the five EEG microstate maps A, B, C, C′ and D, but especially in microstate maps C and C′. These two maps have been linked to neuronal activity in the frontal and parietal brain regions which are associated with working memory and attention, cognitive functions that have been shown to be sensitive to aging. Older adults exhibited lower global explained variance and occurrence of maps C and C′. Moreover, although there was a higher probability to transition from any map towards maps C, C′ and D in young and older adults, this probability was lower in older adults. Finally, although age-related differences in resting-state EEG microstates paralleled differences in allocentric spatial working memory performance, we found no evidence that any individual or combination of resting-state EEG microstate parameter(s) could reliably predict individual spatial working memory performance. Whether the temporal dynamics of EEG microstates may be used to assess healthy cognitive aging from resting-state brain activity requires further investigation.

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Brain hemodynamic response in Examiner–Examinee dyads during spatial short-term memory task: an fNIRS study

Experimental Brain Research ◽

10.1007/s00221-021-06073-0 ◽

2021 ◽

Author(s):

Francesco Panico ◽

Stefania De Marco ◽

Laura Sagliano ◽

Francesca D’Olimpio ◽

Dario Grossi ◽

...

Keyword(s):

Working Memory ◽

Cognitive Processes ◽

Short Term Memory ◽

Spatial Working Memory ◽

Brain Activity ◽

Memory Task ◽

Neural Correlates ◽

Short Term ◽

Term Memory ◽

The Real

AbstractThe Corsi Block-Tapping test (CBT) is a measure of spatial working memory (WM) in clinical practice, requiring an examinee to reproduce sequences of cubes tapped by an examiner. CBT implies complementary behaviors in the examiners and the examinees, as they have to attend a precise turn taking. Previous studies demonstrated that the Prefrontal Cortex (PFC) is activated during CBT, but scarce evidence is available on the neural correlates of CBT in the real setting. We assessed PFC activity in dyads of examiner–examinee participants while completing the real version of CBT, during conditions of increasing and exceeding workload. This procedure allowed to investigate whether brain activity in the dyads is coordinated. Results in the examinees showed that PFC activity was higher when the workload approached or reached participants’ spatial WM span, and lower during workload conditions that were largely below or above their span. Interestingly, findings in the examiners paralleled the ones in the examinees, as examiners’ brain activity increased and decreased in a similar way as the examinees’ one. In the examiners, higher left-hemisphere activity was observed suggesting the likely activation of non-spatial WM processes. Data support a bell-shaped relationship between cognitive load and brain activity, and provide original insights on the cognitive processes activated in the examiner during CBT.

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Abnormal brain activity patterns during spatial working memory task in patients with end-stage renal disease on maintenance hemodialysis: a fMRI study

Brain Imaging and Behavior ◽

10.1007/s11682-020-00383-7 ◽

2020 ◽

Author(s):

Jinzhuang Huang ◽

Lei Xie ◽

Ruiwei Guo ◽

Jinhong Wang ◽

Jinquan Lin ◽

...

Keyword(s):

Working Memory ◽

Frontal Cortex ◽

Spatial Working Memory ◽

Brain Activity ◽

Activity Patterns ◽

Parietal Lobule ◽

Stage Renal Disease ◽

End Stage ◽

Esrd Patients ◽

Back Task

Abstract Hemodialysis (HD) is associated with cognitive impairment in patients with end-stage renal disease (ESRD). However, the neural mechanism of spatial working memory (SWM) impairment in HD-ESRD patients remains unclear. We investigated the abnormal alterations in SWM-associated brain activity patterns in HD-ESRD patients using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) technique during n-back tasks. Twenty-two HD-ESRD patients and 22 well-matched controls underwent an fMRI scan while undergoing a three-load n-back tasks with different difficulty levels. Cognitive and mental states were assessed using a battery of neuropsychologic tests. The HD-ESRD patients exhibited worse memory abilities than controls. Compared with the control group, the HD-ESRD patient group showed lower accuracy and longer response time under the n-back tasks, especially in the 2-back task. The patterns of brain activation changed under different working memory loads in the HD-ESRD patients, showing decreased activity in the right medial frontal gyrus and inferior frontal gyrus under 0-back and 1-back task, while more decreased activation in the bilateral frontal cortex, parietal lobule, anterior/posterior cingulate cortex and insula cortex under 2-back task. With the increase of task difficulty, the activation degree of the frontal and parietal cortex decreased. More importantly, we found that lower activation in frontal cortex and parietal lobule was associated with worse cognitive function in the HD-ESRD patients. These results demonstrate that the abnormal brain activity patterns of frontal cortex and parietal lobule may reflect the neural mediation of SWM impairment.

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Age-Related Differences in Resting-State EEG and Allocentric Spatial Working Memory Performance

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2021.704362 ◽

2021 ◽

Vol 13 ◽

Author(s):

Adeline Jabès ◽

Giuliana Klencklen ◽

Paolo Ruggeri ◽

Jean-Philippe Antonietti ◽

Pamela Banta Lavenex ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Resting State ◽

Spatial Working Memory ◽

Brain Activity ◽

Memory Performance ◽

Group Differences ◽

Age Group ◽

Eeg Activity ◽

Recording Conditions

During normal aging resting-state brain activity changes and working memory performance declines as compared to young adulthood. Interestingly, previous studies reported that different electroencephalographic (EEG) measures of resting-state brain activity may correlate with working memory performance at different ages. Here, we recorded resting-state EEG activity and tested allocentric spatial working memory in healthy young (20–30 years) and older (65–75 years) adults. We adapted standard EEG methods to record brain activity in mobile participants in a non-shielded environment, in both eyes closed and eyes open conditions. Our study revealed some age-group differences in resting-state brain activity that were consistent with previous results obtained in different recording conditions. We confirmed that age-group differences in resting-state EEG activity depend on the recording conditions and the specific parameters considered. Nevertheless, lower theta-band and alpha-band frequencies and absolute powers, and higher beta-band and gamma-band relative powers were overall observed in healthy older adults, as compared to healthy young adults. In addition, using principal component and regression analyses, we found that the first extracted EEG component, which represented mainly theta, alpha and beta powers, correlated with spatial working memory performance in older adults, but not in young adults. These findings are consistent with the theory that the neurobiological bases of working memory performance may differ between young and older adults. However, individual measures of resting-state EEG activity could not be used as reliable biomarkers to predict individual allocentric spatial working memory performance in young or older adults.

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GSK3β inhibition restores cortical gamma oscillation and cognitive behavior in a mouse model of NMDA receptor hypofunction relevant to schizophrenia

Neuropsychopharmacology ◽

10.1038/s41386-020-00819-0 ◽

2020 ◽

Vol 45 (13) ◽

pp. 2207-2218

Author(s):

Kazuhito Nakao ◽

Mahendra Singh ◽

Kiran Sapkota ◽

Bailey C. Hagler ◽

Robert N. Hunter ◽

...

Keyword(s):

Working Memory ◽

Mouse Model ◽

Spatial Working Memory ◽

Gamma Oscillations ◽

Gamma Oscillation ◽

Mutant Mice ◽

Patch Clamp Recording ◽

Behavioral Deficits ◽

Gamma Power ◽

Sensory Evoked

Abstract Cortical gamma oscillations are believed to be involved in mental processes which are disturbed in schizophrenia. For example, the magnitudes of sensory-evoked oscillations, as measured by auditory steady-state responses (ASSRs) at 40 Hz, are robustly diminished, whereas the baseline gamma power is enhanced in schizophrenia. Such dual gamma oscillation abnormalities are also present in a mouse model of N-methyl-D-aspartate receptor hypofunction (Ppp1r2cre/Grin1 knockout mice). However, it is unclear whether the abnormal gamma oscillations are associated with dysfunction in schizophrenia. We found that glycogen synthase kinase-3 (GSK3) is overactivated in corticolimbic parvalbumin-positive GABAergic interneurons in Grin1 mutant mice. Here we addressed whether GSK3β inhibition reverses both abnormal gamma oscillations and behavioral deficits with high correlation by pharmacological and genetic approach. We demonstrated that the paralog selective-GSK3β inhibitor, but not GSK3α inhibitor, normalizes the diminished ASSRs, excessive baseline gamma power, and deficits in spatial working memory and prepulse inhibition (PPI) of acoustic startle in Grin1 mutant mice. Cell-type specific GSK3B knockdown, but not GSK3A knockdown, also reversed abnormal gamma oscillations and behavioral deficits. Moreover, GSK3B knockdown, but not GSK3A knockdown, reverses the mutants’ in vivo spike synchrony deficits. Finally, ex vivo patch-clamp recording from pairs of neighboring cortical pyramidal neurons showed a reduction of synchronous spontaneous inhibitory-postsynaptic-current events in mutants, which was reversed by GSK3β inhibition genetically and pharmacologically. Together, GSK3β inhibition in corticolimbic interneurons ameliorates the deficits in spatial working memory and PPI, presumably by restoration of synchronous GABA release, synchronous spike firing, and evoked-gamma power increase with lowered baseline power.

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Atypical Spatial Working Memory and Task-General Brain Activity in Adolescents with a Family History of Alcoholism

Alcoholism Clinical and Experimental Research ◽

10.1111/j.1530-0277.2012.01948.x ◽

2012 ◽

Vol 37 (3) ◽

pp. 390-398 ◽

Cited By ~ 18

Author(s):

Kristen L. Mackiewicz Seghete ◽

Anita Cservenka ◽

Megan M. Herting ◽

Bonnie J. Nagel

Keyword(s):

Working Memory ◽

Family History ◽

Spatial Working Memory ◽

Brain Activity ◽

History Of ◽

And Task

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Subdiffusive Dynamics of Bump Attractors: Mechanisms and Functional Roles

Neural Computation ◽

10.1162/neco_a_00698 ◽

2015 ◽

Vol 27 (2) ◽

pp. 255-280 ◽

Cited By ~ 4

Author(s):

Yang Qi ◽

Michael Breakspear ◽

Pulin Gong

Keyword(s):

Neural Coding ◽

Spatial Working Memory ◽

Activity Patterns ◽

Stimulus Presentation ◽

Generalized Langevin Equation ◽

Spatial Correlations ◽

Temporal Correlations ◽

Normal Diffusion ◽

Characteristic Features ◽

Noisy Inputs

Bump attractors are localized activity patterns that can self-sustain after stimulus presentation, and they are regarded as the neural substrate for a host of perceptual and cognitive processes. One of the characteristic features of bump attractors is that they are neutrally stable, so that noisy inputs cause them to drift away from their initial locations, severely impairing the accuracy of bump location-dependent neural coding. Previous modeling studies of such noise-induced drifting activity of bump attractors have focused on normal diffusive dynamics, often with an assumption that noisy inputs are uncorrelated. Here we show that long-range temporal correlations and spatial correlations in neural inputs generated by multiple interacting bumps cause them to drift in an anomalous subdiffusive way. This mechanism for generating subdiffusive dynamics of bump attractors is further analyzed based on a generalized Langevin equation. We demonstrate that subdiffusive dynamics can significantly improve the coding accuracy of bump attractors, since the variance of the bump displacement increases sublinearly over time and is much smaller than that of normal diffusion. Furthermore, we reanalyze existing psychophysical data concerning the spread of recalled cue position in spatial working memory tasks and show that its variance increases sublinearly with time, consistent with subdiffusive dynamics of bump attractors. Based on the probability density function of bump position, we also show that the subdiffusive dynamics result in a long-tailed decay of firing rate, greatly extending the duration of persistent activity.

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