scholarly journals Compressed timeline of recent experience in monkey lPFC

2017 ◽  
Author(s):  
Zoran Tiganj ◽  
Jason A. Cromer ◽  
Jefferson E. Roy ◽  
Earl K. Miller ◽  
Marc W. Howard
Keyword(s):  
Working Memory ◽  
Sample Stimulus ◽  
Memory Task ◽  
Empirical Support ◽  
Human Memory ◽  
Basis Functions ◽  
Recent Experience ◽  
Elapsed Time ◽  
Cognitive Theories ◽  
Stimulus Identity

AbstractCognitive theories suggest that working memory maintains not only the identity of recently-presented stimuli but also a sense of the elapsed time since the stimuli were presented. Previous studies of the neural underpinnings of working memory have focused on sustained firing, which can account for maintenance of the stimulus identity, but not for representation of the elapsed time. We analyzed single-unit recordings from the lateral prefrontal cortex (lPFC) of two macaque monkeys during performance of a delayed-match-to-category task. Each sample stimulus triggered a consistent sequence of neurons, with each neuron in the sequence firing during a circumscribed period of time. These sequences of neurons encoded both stimulus identity and the elapsed time. The encoding of the elapsed time became less precise as the sample stimulus receded into the past. These findings suggest that working memory includes a compressed timeline of what happened when, consistent with longstanding cognitive theories of human memory.Significance StatementPlace cells in the hippocampus and other brain regions provide basis functions to support the dimension of physical space. Time cells, which activate sequentially provide analogous support for the dimension of time. We observed time cells in the macaque lPFC during a working memory task. The time cells we observed were stimulus specific meaning that they provide not only information about timing, but also conjunctively code what and when information. This representation thus constitutes a manifold with both temporal dimension and a stimulus-coding dimension that could support working memory. These temporal basis functions maintain a logarithmically-compressed timeline of the recent past, providing strong empirical support to long-standing cognitive theories of human memory.

scholarly journals Compressed Timeline of Recent Experience in Monkey Lateral Prefrontal Cortex

2018 ◽  
Vol 30 (7) ◽  
pp. 935-950 ◽  
Author(s):  
Zoran Tiganj ◽  
Jason A. Cromer ◽  
Jefferson E. Roy ◽  
Earl K. Miller ◽  
Marc W. Howard
Keyword(s):  
Working Memory ◽  
Prefrontal Cortex ◽  
Sample Stimulus ◽  
Human Memory ◽  
Recent Experience ◽  
Lateral Prefrontal Cortex ◽  
Elapsed Time ◽  
Cognitive Theories ◽  
Stimulus Identity ◽  
Neural Underpinnings

Cognitive theories suggest that working memory maintains not only the identity of recently presented stimuli but also a sense of the elapsed time since the stimuli were presented. Previous studies of the neural underpinnings of working memory have focused on sustained firing, which can account for maintenance of the stimulus identity, but not for representation of the elapsed time. We analyzed single-unit recordings from the lateral prefrontal cortex of macaque monkeys during performance of a delayed match-to-category task. Each sample stimulus triggered a consistent sequence of neurons, with each neuron in the sequence firing during a circumscribed period. These sequences of neurons encoded both stimulus identity and elapsed time. The encoding of elapsed time became less precise as the sample stimulus receded into the past. These findings suggest that working memory includes a compressed timeline of what happened when, consistent with long-standing cognitive theories of human memory.

scholarly journals Δ9-Tetrahydrocannabinol (THC) impairs visual working memory performance: A randomized crossover trial

2019 ◽  
Author(s):  
Kirsten C. S. Adam ◽  
Manoj K. Doss ◽  
Elisa Pabon ◽  
Edward K. Vogel ◽  
Harriet de Wit
Keyword(s):  
Working Memory ◽  
Sample Size ◽  
Task Performance ◽  
Visual Working Memory ◽  
Memory Performance ◽  
Memory Task ◽  
Empirical Support ◽  
Mind Wandering ◽  
Double Blind ◽  
Metacognitive Accuracy

AbstractWith the increasing prevalence of legal cannabis use and availability, there is an urgent need to identify cognitive impairments related to its use. It is widely believed that cannabis, or its main psychoactive component Δ9-tetrahydrocannabinol (THC), impairs working memory, i.e., the ability to temporarily hold information in mind. However, our review of the literature yielded surprisingly little empirical support for an effect of THC or cannabis on working memory. We thus conducted a study with 3 main goals: (1) quantify the effect of THC on visual working memory in a well-powered sample (2) test the potential role of cognitive effects (mind wandering and metacognition) in disrupting working memory, and (3) demonstrate how insufficient sample size and task duration reduce the likelihood of detecting a drug effect. We conducted two double-blind, randomized crossover experiments in which healthy adults (N=23, 23) performed a reliable and validated visual working memory task (the “Discrete Whole-Report task”, 90 trials) after administration of THC (7.5 and/or 15 mg oral) or placebo. We also assessed self-reported ‘mind wandering’ (Exp 1) and metacognitive accuracy about ongoing task performance (Exp 2). THC impaired working memory performance (d = .65), increased mind wandering (Exp 1), and decreased metacognitive accuracy about task performance (Exp 2). Thus, our findings indicate that THC does impair visual working memory, and that this impairment may be related to both increased mind-wandering and decreased monitoring of task performance. Finally, we used a down-sampling procedure to illustrate the effects of task length and sample size on power to detect the acute effect of THC on working memory.

The “How” of Animacy Effects in Episodic Memory

2015 ◽  
Vol 62 (6) ◽  
pp. 371-384 ◽  
Author(s):  
Patrick Bonin ◽  
Margaux Gelin ◽  
Betty Laroche ◽  
Alain Méot ◽  
Aurélia Bugaiska
Keyword(s):  
Memory Load ◽  
Recall Performance ◽  
Memory Task ◽  
Human Memory ◽  
Recall Rate ◽  
Interactive Imagery ◽  
Ultimate Explanation ◽  
Better Than ◽  
Observation Results

Abstract. Animates are better remembered than inanimates. According to the adaptive view of human memory ( Nairne, 2010 ; Nairne & Pandeirada, 2010a , 2010b ), this observation results from the fact that animates are more important for survival than inanimates. This ultimate explanation of animacy effects has to be complemented by proximate explanations. Moreover, animacy currently represents an uncontrolled word characteristic in most cognitive research ( VanArsdall, Nairne, Pandeirada, & Cogdill, 2015 ). In four studies, we therefore investigated the “how” of animacy effects. Study 1 revealed that words denoting animates were recalled better than those referring to inanimates in an intentional memory task. Study 2 revealed that adding a concurrent memory load when processing words for the animacy dimension did not impede the animacy effect on recall rates. Study 3A was an exact replication of Study 2 and Study 3B used a higher concurrent memory load. In these two follow-up studies, animacy effects on recall performance were again not altered by a concurrent memory load. Finally, Study 4 showed that using interactive imagery to encode animate and inanimate words did not alter the recall rate of animate words but did increase the recall of inanimate words. Taken together, the findings suggest that imagery processes contribute to these effects.

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