Are there sex differences in brain activity during long-term memory? A systematic review and fMRI activation likelihood estimation meta-analysis

ABSTRACT Background: People use khat (Catha edulis) for its pleasant stimulant effect of physical activity, consciousness, motor, and mental functions. Although there are reports assessing the effect of khat on memory, there was no study based on formal systematic review and meta-analysis. Objective: We have therefore conducted this meta-analysis to determine the level of evidence for the effect of khat (C. edulis Forsk) on memory discrepancy. Methods: MEDLINE, Cochrane Library, PubMed, Academic Search Complete, SPORTDiscus, ScienceDirect, Scopus, Web of Science, and Google Scholar were searched to retrieve the papers for this review. Keywords utilized across database search were khat, cat, chat, long-term memory, short-term memory, memory deficit, randomized control trial, and cross-sectional survey. The search was limited to studies in humans and rodents; published in English language. Result: Finding of various studies included in our meta-analysis showed that the effect of acute, and subchronic exposure to khat showed that short-term memory appears to be affected depending on the duration of exposure. However, does not have any effect on long-term memory. Conclusion: Although a number of studies regarding the current topic are limited, the evidenced showed that khat (C. edulis) induced memory discrepancy.

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Calcium/calmodulin-dependent protein kinase II is a ubiquitous molecule in human long-term memory synaptic plasticity: A systematic review

International Journal of Preventive Medicine ◽

10.4103/2008-7802.164831 ◽

2015 ◽

Vol 6 (1) ◽

pp. 88 ◽

Cited By ~ 12

Author(s):

Ahmad Movahedian ◽

AliMohammad Sabzghabaee ◽

Negar Ataei

Keyword(s):

Systematic Review ◽

Synaptic Plasticity ◽

Protein Kinase ◽

Long Term Memory ◽

Dependent Protein Kinase ◽

Term Memory ◽

Calcium Calmodulin Dependent ◽

Protein Kinase Ii ◽

Dependent Protein

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Thalamic Functional Connectivity during Spatial Long-Term Memory and the Role of Sex

Brain Sciences ◽

10.3390/brainsci10120898 ◽

2020 ◽

Vol 10 (12) ◽

pp. 898

Author(s):

Dylan S. Spets ◽

Scott D. Slotnick

Keyword(s):

Sex Differences ◽

Functional Connectivity ◽

Region Of Interest ◽

Brain Regions ◽

Long Term Memory ◽

Thalamic Nuclei ◽

Term Memory ◽

Correlated Activity ◽

Abstract Shapes

The thalamus has been implicated in many cognitive processes, including long-term memory. More specifically, the anterior (AT) and mediodorsal (MD) thalamic nuclei have been associated with long-term memory. Despite extensive mapping of the anatomical connections between these nuclei and other brain regions, little is known regarding their functional connectivity during long-term memory. The current study sought to determine which brain regions are functionally connected to AT and MD during spatial long-term memory and whether sex differences exist in the patterns of connectivity. During encoding, abstract shapes were presented to the left and right of fixation. During retrieval, shapes were presented at fixation, and participants made an “old-left” or “old-right” judgment. Activations functionally connected to AT and MD existed in regions with known anatomical connections to each nucleus as well as in a broader network of long-term memory regions. Sex differences were identified in a subset of these regions. A targeted region-of-interest analysis identified anti-correlated activity between MD and the hippocampus that was specific to females, which is consistent with findings in rodents. The current results suggest that AT and MD play key roles during spatial long-term memory and suggest that these functions may be sex specific.

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Event-related Functional Magnetic Resonance Imaging of a Low Dose of Dexmedetomidine that Impairs Long-term Memory

Anesthesiology ◽

10.1097/aln.0b013e31826be467 ◽

2012 ◽

Vol 117 (5) ◽

pp. 981-995 ◽

Cited By ~ 16

Author(s):

Hiroki R. Hayama ◽

Kristin M. Drumheller ◽

Mark Mastromonaco ◽

Christopher Reist ◽

Lawrence F. Cahill ◽

...

Keyword(s):

Memory Effect ◽

Drug Exposure ◽

Low Dose ◽

Brain Activity ◽

Statistical Parametric Mapping ◽

Long Term Memory ◽

Term Memory ◽

Picture Memory ◽

Subsequent Memory Effect

Abstract Background Work suggests the amnesia from dexmedetomidine (an α2-adrenergic agonist) is caused by a failure of information to be encoded into long-term memory and that dexmedetomidine might differentially affect memory for emotionally arousing material. We investigated these issues in humans using event-related neuroimaging to reveal alterations in brain activity and subsequent memory effects associated with drug exposure. Methods Forty-eight healthy volunteers received a computer-controlled infusion of either placebo or low-dose dexmedetomidine (target = 0.15 ng/ml plasma) during neuroimaging while they viewed and rated 80 emotionally arousing (e.g., graphic war wound) and 80 nonarousing neutral (e.g., cup) pictures for emotional arousal content. Long-term picture memory was tested 4 days later without neuroimaging. Imaging data were analyzed for drug effects, emotional processing differences, and memory-related changes with statistical parametric mapping-8. Results Dexmedetomidine impaired overall (mean ± SEM) picture memory (placebo: 0.58 ± 0.03 vs. dexmedetomidine: 0.45 ± 0.03, P = 0.001), but did not differentially modulate memory as a function of item arousal. Arousing pictures were better remembered for both groups. Dexmedetomidine had regionally heterogeneous effects on brain activity, primarily decreasing it in the cortex and increasing it in thalamic and posterior hippocampal regions. Nevertheless, a single subsequent memory effect for item memory common to both groups was identified only in the left hippocampus/amygdala. Much of this effect was found to be larger for the placebo than dexmedetomidine group. Conclusion Dexmedetomidine impaired long-term picture memory, but did not disproportionately block memory for emotionally arousing items. The memory impairment on dexmedetomidine corresponds with a weakened hippocampal subsequent memory effect.

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Long-Term Memory Performance in Adult ADHD

Journal of Attention Disorders ◽

10.1177/1087054713510561 ◽

2016 ◽

Vol 21 (4) ◽

pp. 267-283 ◽

Cited By ~ 30

Author(s):

Timo Skodzik ◽

Heinz Holling ◽

Anya Pedersen

Keyword(s):

Visual Memory ◽

Adult Adhd ◽

Memory Performance ◽

Meta Analysis ◽

Long Term Memory ◽

Term Memory ◽

Memory Tests ◽

Memory Acquisition ◽

Meta Analyses

Objective: Memory problems are a frequently reported symptom in adult ADHD, and it is well-documented that adults with ADHD perform poorly on long-term memory tests. However, the cause of this effect is still controversial. The present meta-analysis examined underlying mechanisms that may lead to long-term memory impairments in adult ADHD. Method: We performed separate meta-analyses of measures of memory acquisition and long-term memory using both verbal and visual memory tests. In addition, the influence of potential moderator variables was examined. Results: Adults with ADHD performed significantly worse than controls on verbal but not on visual long-term memory and memory acquisition subtests. The long-term memory deficit was strongly statistically related to the memory acquisition deficit. In contrast, no retrieval problems were observable. Conclusion: Our results suggest that memory deficits in adult ADHD reflect a learning deficit induced at the stage of encoding. Implications for clinical and research settings are presented.

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Neurofeedback Training Improves Long-Term Memory Performance

10.21203/rs.3.rs-413214/v1 ◽

2021 ◽

Author(s):

Yu-Hsuan Tseng ◽

Kaori Tamura ◽

Tsuyoshi Okamoto

Keyword(s):

Semantic Memory ◽

Theta Rhythm ◽

Brain Activity ◽

Human Life ◽

Memory Performance ◽

Control Group ◽

Long Term Memory ◽

Term Memory ◽

Beta Power

Abstract Understanding and improving memory is vital to enhance human life. Theta rhythm is associated with memory consolidation and coding, but the trainability and effects on long-term memory of theta rhythm are unknown. This study investigates the ability to improve long-term memory using a neurofeedback (NFB) technique reflecting the theta/low-beta power ratio on an electroencephalogram (EEG). Our study consisted of three stages: First, the long-term memory of participants was measured. In the second stage, the participants in the NFB group received three days of theta/low-beta NFB training. In the third stage, the long-term memory was measured again. The NFB group had better long-term memory than the control group and significant differences in brain activity between episodic and semantic memory during the recall tests were revealed. These findings suggest that it is possible to improve the long-term memory abilities through theta/low-beta NFB training, which also improves episodic and semantic memory.

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Alpha-band oscillations track the retrieval of precise spatial representations from long-term memory

Journal of Neurophysiology ◽

10.1152/jn.00268.2019 ◽

2019 ◽

Vol 122 (2) ◽

pp. 539-551 ◽

Cited By ~ 3

Author(s):

David W. Sutterer ◽

Joshua J. Foster ◽

John T. Serences ◽

Edward K. Vogel ◽

Edward Awh

Keyword(s):

Memory Retrieval ◽

Time Course ◽

Brain Activity ◽

Initial Study ◽

Long Term Memory ◽

Spatial Representations ◽

Alpha Band ◽

Term Memory ◽

Spatial Memories

A hallmark of episodic memory is the phenomenon of mentally reexperiencing the details of past events, and a well-established concept is that the neuronal activity that mediates encoding is reinstated at retrieval. Evidence for reinstatement has come from multiple modalities, including functional magnetic resonance imaging and electroencephalography (EEG). These EEG studies have shed light on the time course of reinstatement but have been limited to distinguishing between a few categories. The goal of this work was to use recently developed experimental and technical approaches, namely continuous report tasks and inverted encoding models, to determine which frequencies of oscillatory brain activity support the retrieval of precise spatial memories. In experiment 1, we establish that an inverted encoding model applied to multivariate alpha topography tracks the retrieval of precise spatial memories. In experiment 2, we demonstrate that the frequencies and patterns of multivariate activity at study are similar to the frequencies and patterns observed during retrieval. These findings highlight the broad potential for using encoding models to characterize long-term memory retrieval. NEW & NOTEWORTHY Previous EEG work has shown that category-level information observed during encoding is recapitulated during memory retrieval, but studies with this time-resolved method have not demonstrated the reinstatement of feature-specific patterns of neural activity during retrieval. Here we show that EEG alpha-band activity tracks the retrieval of spatial representations from long-term memory. Moreover, we find considerable overlap between the frequencies and patterns of activity that track spatial memories during initial study and at retrieval.

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A Systematic Review and Activation Likelihood Estimation Meta-Analysis of fMRI Studies on Sweet Taste in Humans

Journal of Nutrition ◽

10.1093/jn/nxaa071 ◽

2020 ◽

Vol 150 (6) ◽

pp. 1619-1630

Author(s):

Carl A Roberts ◽

Timo Giesbrecht ◽

Nicholas Fallon ◽

Anna Thomas ◽

David J Mela ◽

...

Keyword(s):

Systematic Review ◽

Meta Analysis ◽

Likelihood Estimation ◽

Sweet Taste ◽

Neural Representation ◽

Sensitivity Analyses ◽

Activation Likelihood Estimation ◽

Data Set ◽

Brain Responses ◽

Human Adults

ABSTRACT Background The reward value of palatable foods is often cited as an important influence on eating behaviors, including intake of sugars. However, human neuroimaging studies have generated conflicting evidence on the basic neural representation of taste and reward responses to caloric sweeteners (sucrose and glucose), and most relevant studies have used small subject numbers. Objective We conducted a systematic review and a coordinate-based meta-analysis of studies reporting brain responses to oral sugar solutions. Methods A systematic search of MEDLINE, Scopus, and PsycINFO through October 2019 identified fMRI studies (in healthy human adults, including those with overweight or obesity) assessing differences in responses to purified sweet and nonsweet taste stimuli. Data were extracted with the primary objective of quantifying evidence for the activation of brain regions associated with caloric sweet taste sensation. We used activation likelihood estimation meta-analysis methods. We also performed multiple sensitivity analyses to assess the generality of effects. Results Of 455 unique articles, 15 met the criteria for inclusion. These contributed to 2 primary meta-analyses: 1) sucrose (13 experiments, 179 coordinates, n = 241) and 2) sucrose + glucose (16 experiments, 209 coordinates, n = 262). Consistent activation was apparent in primary taste areas: insula (69.2% of studies) and opercular cortex (76.9% of studies), precentral gyri (53.9% of studies), and globus pallidus and postcentral gyrus (30.8% of studies for each). Evidence of reward activity (caudate) was seen in the primary analyses (30.8% of studies) but not in sensitivity analysis. Conclusions We confirm the importance of primary taste areas for gustatory processing in human adults. We also provide tentative evidence for reward-related caudate activity in relation to the sweet taste of caloric sugars. A number of factors affect the observation and interpretation of brain responses, including reward-related activity. Firm conclusions require confirmation with large data set studies.

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