Influences of Instructions and Expertise on the Mechanisms Involved During a Working Memory Task

The purpose of this study was to examine the effects of instructions and expertise upon cortical mechanisms during a working memory task. Ten professional pianists and ten musically naïve subjects were instructed to retain for a short period of time, sequential finger movements viewed previously with the aim of either replicating them or recognizing them at a later stage. The results showed that in the 20–30 Hz frequency band and in musically naïve subjects, functional connectivity was greater within the occipital, parietal, central, frontal, right, and left temporal areas when the subjects were invited to remember the observed movement in order to replicate it compared to the recognition condition in which they had to recognize it. In professional pianists, incomplete connectivity equivalence was detected between the two conditions. In addition, under the condition for replica, functional connectivity in musically naïve subjects was greater in the central area compared to professional pianists. Explanations related to the: (i) level of expertise, (ii) nature of operations involved during the retention period, and (iii) task demand are discussed.

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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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Declined functional connectivity of white matter during rest and working memory tasks associates with cognitive impairments in schizophrenia

10.1101/2020.05.16.20091397 ◽

2020 ◽

Cited By ~ 1

Author(s):

Yurui Gao ◽

Muwei Li ◽

Anna S Huang ◽

Adam W Anderson ◽

Zhaohua Ding ◽

...

Keyword(s):

Working Memory ◽

White Matter ◽

Functional Connectivity ◽

Resting State ◽

Spatial Working Memory ◽

Cognitive Impairments ◽

Memory Task ◽

Brain Network ◽

Blood Oxygenation ◽

Cerebral Peduncle

BACKGROUND: Schizophrenia, characterized by cognitive impairments, arises from a disturbance of brain network. Pathological changes in white matter (WM) have been indicated as playing a role in disturbing neural connectivity in schizophrenia. However, deficits of functional connectivity (FC) in individual WM bundles in schizophrenia have never been explored; neither have cognitive correlates with those deficits. METHODS: Resting-state and spatial working memory task fMRI images were acquired on 67 healthy subjects and 84 patients with schizophrenia. The correlations in blood-oxygenation-level-dependent (BOLD) signals between 46 WM and 82 gray matter regions were quantified, analyzed and compared between groups under three scenarios (i.e., resting state, retention period and entire time of a spatial working memory task). Associations of FC in WM with cognitive assessment scores were evaluated for three scenarios. RESULTS: FC deficits were significant (p<.05) in external capsule, cingulum, uncinate fasciculus, genu and body of corpus callosum under all three scenarios. Deficits were also present in the anterior limb of the internal capsule and cerebral peduncle in task scenario. Decreased FCs in specific WM bundles associated significantly (p<.05) with cognitive impairments in working memory, processing speed and/or cognitive control. CONCLUSIONS: Decreases in FC are evident in several WM bundles in patients with schizophrenia and are significantly associated with cognitive impairments during both rest and working memory tasks. Furthermore, working memory tasks expose FC deficits in more WM bundles and more cognitive associates in schizophrenia than resting state does.

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Practice with a working memory task changes functional connectivity during the rest period preceding the task

NeuroImage ◽

10.1016/s1053-8119(09)71771-9 ◽

2009 ◽

Vol 47 ◽

pp. S166

Author(s):

DD Jolles ◽

MJ Grol ◽

MA Van Buchem ◽

EA Crone ◽

SARB Rombouts

Keyword(s):

Working Memory ◽

Functional Connectivity ◽

Memory Task ◽

Rest Period

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Functional Connectivity Analysis from Multi Spike Trains on Prefrontal Cortex of Rat during Working Memory Task

2012 Fifth International Symposium on Computational Intelligence and Design ◽

10.1109/iscid.2012.96 ◽

2012 ◽

Author(s):

Dexuan Qi ◽

Zhenguo Xiao ◽

Xin Tian

Keyword(s):

Working Memory ◽

Prefrontal Cortex ◽

Functional Connectivity ◽

Memory Task ◽

Spike Trains ◽

Connectivity Analysis ◽

Functional Connectivity Analysis

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Functional Connectivity Analysis from Theta Band of Multi Local Field Potentials on Prefrontal Cortex of Rat during Working Memory Task

2017 9th International Conference on Intelligent Human-Machine Systems and Cybernetics (IHMSC) ◽

10.1109/ihmsc.2017.14 ◽

2017 ◽

Cited By ~ 1

Author(s):

Dexuan Qi ◽

Zhenguo Xiao ◽

Shuo Liu ◽

Yongshu Jiao

Keyword(s):

Working Memory ◽

Prefrontal Cortex ◽

Functional Connectivity ◽

Local Field ◽

Memory Task ◽

Local Field Potentials ◽

Field Potentials ◽

Connectivity Analysis ◽

Theta Band ◽

Functional Connectivity Analysis

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No evidence for changes in GABA concentration, functional connectivity, or working memory following continuous theta burst stimulation over dorsolateral prefrontal cortex

10.1101/2021.06.17.448448 ◽

2021 ◽

Author(s):

Tribikram Thapa ◽

Joshua Hendrikse ◽

Sarah Thompson ◽

Chao Suo ◽

Mana Biabani ◽

...

Keyword(s):

Working Memory ◽

Functional Connectivity ◽

Memory Performance ◽

Memory Task ◽

Low Frequency ◽

Theta Burst Stimulation ◽

Gaba Concentration ◽

Dorsolateral Prefrontal ◽

Theta Burst ◽

Continuous Theta Burst Stimulation

Continuous theta burst stimulation (cTBS) is thought to reduce cortical excitability and modulate functional connectivity, possibly by altering cortical inhibition at the site of stimulation. However, most evidence comes from the motor cortex and it remains unclear whether similar effects occur following stimulation over other brain regions. We assessed whether cTBS over left dorsolateral prefrontal cortex altered gamma aminobutyric acid (GABA) concentration, functional connectivity and brain dynamics at rest, and brain activation and memory performance during a working memory task. Seventeen healthy individuals participated in a randomised, sham-controlled, cross-over experiment. Before and after either real or sham cTBS, magnetic resonance spectroscopy was obtained at rest to measure GABA concentrations, whereas functional magnetic resonance imaging (fMRI) was recorded at rest and during an n-back working memory task to measure functional connectivity, brain dynamics (low-frequency fluctuations), and task-related patterns of brain activity. We could not find evidence for changes in GABA concentration (P=0.66, Bayes factor [BF10]=0.07), resting-state functional connectivity (P(FWE)>0.05), resting-state low-frequency fluctuations (P=0.88, BF10=0.04), blood-oxygen level dependent activity during the n-back task (P(FWE) >0.05), or working memory performance (P=0.13, BF10=0.05) following real or sham cTBS. Our findings add to a growing body of literature suggesting the effects of cTBS are highly variable between individuals and question the notion that cTBS is a universal 'inhibitory' paradigm.

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