scholarly journals Benchmarking GE-BOLD, SE-BOLD, and SS-SI-VASO sequences for depth-dependent separation of feedforward and feedback signals in high-field MRI

2021 ◽  
Author(s):  
Polina Iamshchinina ◽  
Daniel Haenelt ◽  
Robert Trampel ◽  
Nikolaus Weiskopf ◽  
Daniel Kaiser ◽  
...  
Keyword(s):  
Working Memory ◽  
High Field ◽  
Spin Echo ◽  
Memory Task ◽  
Feedback Information ◽  
Perception Task ◽  
Color Changes ◽  
Early Visual Cortex ◽  
Memory Signals ◽  
Mr Sequences

Recent advances in high-field fMRI have allowed differentiating feedforward and feedback information in the grey matter of the human brain. For continued progress in this endeavor, it is critical to understand how MRI data acquisition parameters impact the read-out of information from laminar response profiles. Here, we benchmarked three different MR-sequences at 7T - gradient-echo (GE), spin-echo (SE) and vascular space occupancy imaging (VASO) - in differentiating feedforward and feedback signals in human early visual cortex (V1). The experiment (N=4) consisted of two complementary tasks: a perception task that predominantly evokes feedforward signals and a working memory task that relies on feedback signals. In the perception task, participants saw flickering oriented gratings while detecting orthogonal color-changes. In the working memory task, participants memorized the precise orientation of a grating. We used multivariate pattern analysis to read out the perceived (feedforward) and memorized (feedback) grating orientation from neural signals across cortical depth. Analyses across all the MR-sequences revealed perception signals predominantly in the middle cortical compartment of area V1 and working memory signals in the deep compartment. Despite an overall consistency across sequences, SE-EPI was the only sequence where both feedforward and feedback information were differently pronounced across cortical depth in a statistically robust way. We therefore suggest that in the context of a typical cognitive neuroscience experiment as the one benchmarked here, SE-EPI may provide a favorable trade-off between spatial specificity and signal sensitivity.

scholarly journals Measuring memory is harder than you think: A crisis of measurement in memory research

2021 ◽  
Author(s):  
Timothy F. Brady ◽  
Maria Martinovna Robinson ◽  
Jamal Rodgers Williams ◽  
John Wixted
Keyword(s):  
Working Memory ◽  
False Alarm ◽  
False Alarm Rate ◽  
Eyewitness Identification ◽  
Memory Performance ◽  
Memory Task ◽  
Theory And Practice ◽  
Memory Research ◽  
Hit Rate ◽  
Memory Signals

There is a crisis of measurement in memory research, with major implications for theory and practice. This crisis arises because of a critical complication present when measuring memory using the recognition memory task that dominates the study of working memory and long-term memory (“did you see this item? yes/no” or “did this item change? yes/no”). Such tasks give two measures of performance, the “hit rate” (how often you say you previously saw an item you actually did previously see) and the “false alarm rate” (how often you say you saw something you never saw). Yet what researchers want is one single, integrated measure of memory performance. Integrating the hit and false alarm rate into a single measure, however, requires a complex problem of counterfactual reasoning that depends on the (unknowable) distribution of underlying memory signals: when faced with two people differing in both hit rate and false alarm rate, the question of who had the better memory is really “who would have had more hits if they each had the same number of false alarms”. As a result of this difficulty, different literatures in memory research (e.g., visual working memory, eyewitness identification, picture memory, etc) have settled on a variety of distinct metrics to combine hit rates and false alarm rates (e.g., A’, corrected hit rate, percent correct, d’, diagnosticity ratios, K values, etc.). These metrics make different, contradictory assumptions about the distribution of latent memory signals, and all of their assumptions are frequently incorrect. Despite a large literature on how to properly measure memory performance, spanning decades, real-life decisions are often made using these metrics, even when they subsequently turn out to be wrong when memory is studied with better measures. We suggest that in order for the psychology and neuroscience of memory to become a cumulative, theory-driven science, more attention must be given to measurement issues. We make a concrete suggestion: the default memory task should change from old/new (“did you see this item’?”) to forced-choice (“which of these two items did you see?”). In situations where old/new variants are preferred (e.g., eyewitness identification; theoretical investigations of the nature of memory decisions), receiver operating characteristic (ROC) analysis should always be performed.

scholarly journals Layer-specificity in the effects of attention and working memory on activity in primary visual cortex

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Timo van Kerkoerle ◽  
Matthew W. Self ◽  
Pieter R. Roelfsema
Keyword(s):  
Working Memory ◽  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Neuronal Activity ◽  
Current Source ◽  
Memory Task ◽  
Neuronal Firing ◽  
Top Down ◽  
Attention Task ◽  
Early Visual Cortex

Abstract Neuronal activity in early visual cortex depends on attention shifts but the contribution to working memory has remained unclear. Here, we examine neuronal activity in the different layers of the primary visual cortex (V1) in an attention-demanding and a working memory task. A current-source density analysis reveales top-down inputs in the superficial layers and layer 5, and an increase in neuronal firing rates most pronounced in the superficial and deep layers and weaker in input layer 4. This increased activity is strongest in the attention task but it is also highly reliable during working memory delays. A visual mask erases the V1 memory activity, but it reappeares at a later point in time. These results provide new insights in the laminar circuits involved in the top-down modulation of activity in early visual cortex in the presence and absence of visual stimuli.

scholarly journals Flexible utilization of spatial- and motor-based codes for the storage of visuo-spatial information

2021 ◽  
Author(s):  
Margaret M. Henderson ◽  
Rosanne L. Rademaker ◽  
John T. Serences
Keyword(s):  
Working Memory ◽  
Visual Information ◽  
Spatial Information ◽  
Spatial Working Memory ◽  
Premotor Cortex ◽  
Memory Task ◽  
Alternative View ◽  
Visual Spatial ◽  
Early Visual Cortex ◽  
Visual Spatial Working Memory

Working memory (WM) provides flexible storage of information in service of upcoming behavioral goals. Some models propose specific fixed loci and mechanisms for the storage of visual information in WM, such as sustained spiking in parietal and prefrontal cortex during the maintenance of features. An alternative view is that information can be remembered in a flexible format that best suits current behavioral goals. For example, remembered visual information might be stored in sensory areas for easier comparison to future sensory inputs (i.e. a retrospective code) or might be remapped into a more abstract, output-oriented format and stored in motor areas (i.e. a prospective code). Here, we tested this hypothesis using a visual-spatial working memory task where the required behavioral response was either known or unknown during the memory delay period. Using fMRI and multivariate decoding, we found that there was less information about remembered spatial positions in early visual and parietal regions when the required response was known versus unknown. Further, a representation of the planned motor action emerged in primary somatosensory, primary motor, and premotor cortex on the same trials where spatial information was reduced in early visual cortex. These results suggest that the neural networks supporting WM can be strategically reconfigured depending on the specific behavioral requirements of canonical visual WM paradigms.

Articulatory Suppression Increases Proactive and Semantic Interference in a Working Memory Task

2008 ◽  
Author(s):  
Alexandra S. Atkins ◽  
Marc G. Berman ◽  
John Jonides ◽  
Patricia A. Reuterlorenz
Keyword(s):  
Working Memory ◽  
Articulatory Suppression ◽  
Memory Task ◽  
Semantic Interference

Mindfulness Training as Cognitive Training in High-Demand Cohorts: An Initial Study in Elite Military Servicemembers

2018 ◽  
Author(s):  
Anthony Paul Zanesco ◽  
Ekaterina Denkova ◽  
Scott L. Rogers ◽  
William K. MacNulty ◽  
Amishi P. Jha
Keyword(s):  
Working Memory ◽  
Cognitive Training ◽  
Short Form ◽  
Memory Performance ◽  
Memory Task ◽  
Selection Criterion ◽  
Initial Study ◽  
Mindfulness Training ◽  
Training Tool ◽  
Cognitive Failures

Cognitive ability is a key selection criterion for entry into many elite professions. Herein, we investigate whether mindfulness training (MT) can enhance cognitive performance in elite military forces. The cognitive effects of a short-form 8-hour MT program contextualized for military cohorts, referred to as Mindfulness-Based Attention Training (MBAT), were assessed. Servicemembers received either a 2-week (n = 40) or 4-week (n = 36) version of MBAT, or no training (NTC, n = 44). Sustained attention and working memory task performance along with self-reported cognitive failures were assessed at study onset (T1) and 8-weeks later (T2). In contrast to both the NTC and 2-week MT groups, the 4-week MT group significantly improved over time on attention and working memory outcome measures. Among the 4-week more so than the 2-week MBAT participants, working memory performance improvements were correlated with their amount of out-of-class MT practice. In addition to these group-wise effects, all participants receiving MBAT decreased in their self-reported cognitive failures from T1 to T2. Importantly, none of these improvements were related to self-reported task motivation. Together, these results suggest that short-form MT, when delivered over a 4-week delivery schedule, may be an effective cognitive training tool in elite military cohorts.

scholarly journals Task Monitoring and Working Memory as Executive Components Predictive of General and Specific Academic Achievements in 6–9-Year-Old Children

2021 ◽  
Vol 18 (13) ◽  
pp. 6681
Author(s):  
Alberto Quílez-Robres ◽  
Nieves Moyano ◽  
Alejandra Cortés-Pascual
Keyword(s):  
Academic Achievement ◽  
Working Memory ◽  
Academic Performance ◽  
Executive Functions ◽  
Language Arts ◽  
Memory Task ◽  
Academic Achievements ◽  
Predictive Role ◽  
And Mathematics ◽  
The Relationship

Academic achievement has been linked to executive functions. However, it is necessary to clarify the different predictive role that executive functions have on general and specific academic achievement and to determine the most predictive executive factor of this academic achievement. The relationship and predictive role between executive functions and their components (initiative, working memory, task monitoring, organization of materials, flexibility, emotional control, inhibition, self-monitoring) with academic achievement are analyzed in this study, both globally and specifically in the areas of Language Arts and Mathematics, in 133 students from 6 to 9 years of age. The relationship obtained in Pearson’s correlation analysis does not differ substantially between overall achievement (r = 0.392) and specific achievement (r = 0.361, r = 0.361), but task monitoring (r = 0.531, r = 0.455, r = 0.446) and working memory (r = 0.512, r = 0.475, r = 0.505) had a greater relationship with general and specific achievement. Finally, regression analyses based on correlation results indicate that executive functions predict general academic performance (14.7%) and specific performance (12.3%, 12.2%) for Language Arts and Mathematics, respectively. Furthermore, working memory and task supervision represent 32.5% of general academic performance, 25.5% of performance in Language Arts, and 27.1% of performance in Mathematics. In conclusion, this study yielded exploratory data on the possible executive functions (task supervision and working memory) responsible for good general academic achievements and specific academic achievements in Mathematics and Language Arts.

Sign in / Sign up

Export Citation Format

Share Document