scholarly journals EEG biomarkers of free recall

2021 ◽  
Author(s):  
Michael J. Kahana ◽  
Brandon S. Katerman ◽  
Connor Keane ◽  
Yuxuan Li ◽  
Jessie K. Pazdera
Keyword(s):  
Cognitive Processes ◽  
Memory Retrieval ◽  
Brain Activity ◽  
Gamma Activity ◽  
Episodic Retrieval ◽  
Neural Signals ◽  
Verbal Recall ◽  
Immediate Recall ◽  
Gamma Power ◽  
Successful Recall

Brain activity in the moments leading up to successful verbal recall provide a window into the cognitive processes underlying memory retrieval. But these same recordings also subsume neural signals unrelated to mnemonic retrieval, such as response-related motor activity. Here we examined spectral EEG biomarkers of successful recall under an extreme manipulation of mnemonic demands: subjects either recalled items after a few seconds or several days. This manipulation isolated EEG components specifically re- lated to episodic retrieval. Theta and gamma power (4-8 Hz and 40-128 Hz respectively) increased immediately prior to long-delay recall, whereas 8-20 Hz power decreased. A direct comparison of long-delay and immediate recall revealed a nearly identical pattern, indicating that these spectral biomarkers of successful retrieval reflect memory-specific processes. Ruling out a confound of motor related activity, these results identify theta and gamma activity as biomarkers of successful episodic memory retrieval.

Frontal Brain Activity during Episodic and Semantic Retrieval: Insights from Event-Related Potentials

1999 ◽  
Vol 11 (6) ◽  
pp. 598-609 ◽  
Author(s):  
Charan Ranganath ◽  
Ken A. Paller
Keyword(s):  
Prefrontal Cortex ◽  
Memory Retrieval ◽  
Brain Activity ◽  
Novelty Detection ◽  
Event Related Potentials ◽  
Episodic Retrieval ◽  
Semantic Retrieval ◽  
Retrieval Task ◽  
Related Potentials ◽  
The Right

Previous neuropsychological and neuroimaging results have implicated the prefrontal cortex in memory retrieval, although its precise role is unclear. In the present study, we examined patterns of brain electrical activity during retrieval of episodic and semantic memories. In the episodic retrieval task, participants retrieved autobiographical memories in response to event cues. In the semantic retrieval task, participants generated exemplars in response to category cues. Novel sounds presented intermittently during memory retrieval elicited a series of brain potentials including one identifiable as the P3a potential. Based on prior research linking P3a with novelty detection and with the frontal lobes, we predicted that P3a would be reduced to the extent that novelty detection and memory retrieval interfere with each other. Results during episodic and semantic retrieval tasks were compared to results during a task in which subjects attended to the auditory stimuli. P3a amplitudes were reduced during episodic retrieval, particularly at right lateral frontal scalp locations. A similar but less lateralized pattern of frontal P3a reduction was observed during semantic retrieval. These findings support the notion that the right prefrontal cortex is engaged in the service of memory retrieval, particularly for episodic memories.

A Preliminary Study of the Association Among Metacognition and Resting State EEG in Schizophrenia

2016 ◽  
Vol 30 (2) ◽  
pp. 47-54 ◽  
Author(s):  
Jenifer L. Vohs ◽  
Bethany L. Leonhardt ◽  
Michael M. Francis ◽  
Daniel Westfall ◽  
Josselyn Howell ◽  
...  
Keyword(s):  
Resting State ◽  
Brain Activity ◽  
Gamma Activity ◽  
Multiple Perspectives ◽  
Behavioral Correlates ◽  
Form Complex ◽  
Gamma Frequency ◽  
Gamma Range ◽  
The World ◽  
Gamma Power

Abstract. Metacognition refers to a spectrum of activities that range from the consideration of discrete mental experiences, such as a specific thought or emotion, to the synthesis of discrete perceptions into integrated representations of the self and others as unique agents in the world. Metacognitive deficits have been observed in schizophrenia and linked with a number of behavioral correlates and outcomes. Less is known however about the neural systems associated with such processes. Establishing the link between brain activity and metacognition therefore is an essential next step. Resting state electroencephalography (EEG) provides one possible avenue for investigating this link. EEG studies in schizophrenia suggest that the gamma frequency range may have functional significance and be related to the disturbed information processing often observed in the disorder. In the present investigation, we assessed metacognition among 20 individuals with prolonged schizophrenia using the Metacognition Assessment Scale Abbreviated, who also participated in resting state EEG recording. We hypothesized that gamma activity would be associated with those domains of metacognition that require the most integration to perform, Decentration and Mastery. We then examined the association among gamma power and each metacognitive domain. Additional exploratory analyses were conducted across a spectrum of EEG activity. We found that increased gamma activity at rest was linked with decreased decentration. This suggests that hyperactivity in the gamma range may index disrupted processing and integration, and ultimately the metacognitive processes needed to form complex ideas about oneself and others and to see the world from multiple perspectives. This link provides additional evidence of how the biological roots of schizophrenia may culminate in a disrupted life.

scholarly journals Core Network Contributions to Remembering the Past, Imagining the Future, and Thinking Creatively

2018 ◽  
Vol 30 (12) ◽  
pp. 1939-1951 ◽  
Author(s):  
Roger E. Beaty ◽  
Preston P. Thakral ◽  
Kevin P. Madore ◽  
Mathias Benedek ◽  
Daniel L. Schacter
Keyword(s):  
Episodic Memory ◽  
Memory Retrieval ◽  
Divergent Thinking ◽  
Brain Activity ◽  
Inferior Frontal Gyrus ◽  
Parahippocampal Gyrus ◽  
Episodic Retrieval ◽  
Core Network ◽  
Creative Cognition ◽  
The Core

The core network refers to a set of neural regions that have been consistently associated with episodic memory retrieval and episodic future simulation. This network is thought to support the constructive thought processes that allow the retrieval and flexible combination of stored information to reconstruct past and construct novel future experiences. Recent behavioral research points to an overlap between these constructive processes and those also engaged during divergent thinking—the ability to think creatively and generate novel ideas—but the extent to which they involve common neural correlates remains unclear. Using fMRI, we sought to address this question by assessing brain activity as participants recalled past experiences, simulated future experiences, or engaged in divergent thinking. Consistent with past work, we found that episodic retrieval and future simulation activated the core network compared with a semantic control condition. Critically, a triple conjunction of episodic retrieval, future simulation, and divergent thinking revealed common engagement of core network regions, including the bilateral hippocampus and parahippocampal gyrus, as well as other regions involved in memory retrieval (inferior frontal gyrus) and mental imagery (middle occipital gyrus). The results provide further insight into the roles of the hippocampus and the core network in episodic memory retrieval, future simulation, and divergent thinking and extend recent work highlighting the involvement of constructive episodic processes in creative cognition.

scholarly journals Delta-range coupling between prefrontal cortex and hippocampus supported by respiratory rhythmic input from the olfactory bulb in freely behaving rats

2020 ◽  
Author(s):  
Rola Mofleh ◽  
Bernat Kocsis
Keyword(s):  
Prefrontal Cortex ◽  
Olfactory Bulb ◽  
Cognitive Processes ◽  
Phase Modulation ◽  
Brain Activity ◽  
Current Source ◽  
Gamma Activity ◽  
Density Analysis ◽  
Freely Behaving ◽  
The Common

Abstract An explosion of recent findings firmly demonstrated that brain activity and cognitive function in rodents and humans are modulated synchronously with nasal respiration. Rhythmic respiratory (RR) coupling of wide-spread forebrain activity was confirmed using advanced techniques, including current source density analysis, single unit firing, and phase modulation of local gamma activity, creating solid premise for investigating how higher networks use this mechanism in their communication. Here we show essential differences in the way prefrontal cortex (PFC) and hippocampus (HC) process the RR signal from the olfactory bulb (OB) allowing dynamic PFC-HC coupling utilizing this input. We used inter-regional coherences and their correlations in rats, breathing at low rate (~ 2 Hz) at rest, outside of the short sniffing bouts. We found strong and stable OB-PFC coherence, contrasting OB-HC coherence which was low but highly variable. PFC-HC coupling, however, primarily correlated with the latter, indicating that HC access to the PFC output is dynamically regulated by the responsiveness of HC to the common rhythmic drive. This pattern was present in both theta and non-theta states of waking, whereas PFC-HC communication appeared protected from RR synchronization in sleep states. The findings help to understand the mechanism of rhythmic modulation of non-olfactory cognitive processes by the on-going regular respiration, reported in rodents as well as humans. These mechanisms may also be important to understand how OB-pathology may lead to neurological consequences, similar to known olfactory disturbances in COVID-19.

scholarly journals Delta-range coupling between prefrontal cortex and hippocampus supported by respiratory rhythmic input from the olfactory bulb in freely behaving rats

2020 ◽  
Author(s):  
Rola Mofleh ◽  
Bernat Kocsis
Keyword(s):  
Prefrontal Cortex ◽  
Olfactory Bulb ◽  
Cognitive Processes ◽  
Phase Modulation ◽  
Brain Activity ◽  
Current Source ◽  
Gamma Activity ◽  
Density Analysis ◽  
Freely Behaving ◽  
The Common

Abstract An explosion of recent findings firmly demonstrated that brain activity and cognitive function in rodents and humans are modulated synchronously with nasal respiration. Rhythmic respiratory (RR) coupling of wide-spread forebrain activity was confirmed using advanced techniques, including current source density analysis, single unit firing, and phase modulation of local gamma activity, creating solid premise for investigating how higher networks use this mechanism in their communication. Here we show essential differences in the way prefrontal cortex (PFC) and hippocampus (HC) process the RR signal from the olfactory bulb (OB) allowing dynamic PFC-HC coupling utilizing this input. We used inter-regional coherences and their correlations in rats, breathing at low rate (~2 Hz) at rest, outside of the short sniffing bouts. We found strong and stable OB-PFC coherence, contrasting OB-HC coherence which was low but highly variable. PFC-HC coupling, however, primarily correlated with the latter, indicating that HC access to the PFC output is dynamically regulated by the responsiveness of HC to the common rhythmic drive. This pattern was present in both theta and non-theta states of waking, whereas PFC-HC communication appeared protected from RR synchronization in sleep states. The findings help to understand the mechanism of rhythmic modulation of non-olfactory cognitive processes by the on-going regular respiration, reported in rodents as well as humans. These mechanisms may also be important to understand how OB-pathology may lead to neurological consequences, similar to known olfactory disturbances in COVID-19.

scholarly journals Psychological, Neurophysiological, and Mental Factors Associated With Gamma-Enhancing Neurofeedback Success

2020 ◽  
Vol 11 (5) ◽  
pp. 701-714
Author(s):  
Zeynab Khodakarami ◽  
◽  
Mohammad Firoozabadi ◽  
Keyword(s):  
Fluid Intelligence ◽  
Brain Activity ◽  
Cognitive Task ◽  
Gain Control ◽  
Learning Performance ◽  
Gamma Activity ◽  
Alpha Power ◽  
Neurofeedback Training ◽  
Eyes Closed ◽  
Gamma Power

Introduction: Regarding the neurofeedback training process, previous studies indicate that 10%-50% of subjects cannot gain control over their brain activity even after repeated training sessions. This study is conducted to overcome this problem by investigating inter-individual differences in neurofeedback learning to propose some predictors for the trainability of subjects. Methods: Eight healthy female students took part in 8 (electroencephalography) EEG neurofeedback training sessions for enhancing EEG gamma power at the Oz channel. We studied participants’ preexisting fluid intelligence and EEG frequency sub-bands’ power during 2-min eyes-closed rest and a cognitive task as psychological and neurophysiological factors, concerning neurofeedback learning performance. We also assessed the self-reports of participants about mental strategies used by them during neurofeedback to identify the most effective successful strategies. Results: The results revealed that a significant percentage of individuals (25% in this study) cannot learn how to control their brain gamma activity using neurofeedback. Our findings suggest that fluid intelligence, gamma power during a cognitive task, and alpha power at rest can predict gamma-enhancing neurofeedback performance of individuals. Based on our study, neurofeedback learning is a form of implicit learning. We also found that learning without a user’s mental efforts to find out successful mental strategies, in other words, unconscious learning, lead to more success in gamma-enhancing neurofeedback. Conclusion: Our results may improve gamma neurofeedback efficacy for further clinical usage and studies by giving insight about both non-trainable individuals and effective mental strategies.

Inefficient Encoding as an Explanation for Age-Related Deficits in Recollection-Based Processing

2014 ◽  
Vol 28 (3) ◽  
pp. 148-161 ◽  
Author(s):  
David Friedman ◽  
Ray Johnson
Keyword(s):  
Older Adults ◽  
Young Adults ◽  
Cognitive Processes ◽  
Brain Activity ◽  
Memory Performance ◽  
Brain Regions ◽  
Semantic Retrieval ◽  
Age Related ◽  
The Face ◽  
Episodic Memories

A cardinal feature of aging is a decline in episodic memory (EM). Nevertheless, there is evidence that some older adults may be able to “compensate” for failures in recollection-based processing by recruiting brain regions and cognitive processes not normally recruited by the young. We review the evidence suggesting that age-related declines in EM performance and recollection-related brain activity (left-parietal EM effect; LPEM) are due to altered processing at encoding. We describe results from our laboratory on differences in encoding- and retrieval-related activity between young and older adults. We then show that, relative to the young, in older adults brain activity at encoding is reduced over a brain region believed to be crucial for successful semantic elaboration in a 400–1,400-ms interval (left inferior prefrontal cortex, LIPFC; Johnson, Nessler, & Friedman, 2013 ; Nessler, Friedman, Johnson, & Bersick, 2007 ; Nessler, Johnson, Bersick, & Friedman, 2006 ). This reduced brain activity is associated with diminished subsequent recognition-memory performance and the LPEM at retrieval. We provide evidence for this premise by demonstrating that disrupting encoding-related processes during this 400–1,400-ms interval in young adults affords causal support for the hypothesis that the reduction over LIPFC during encoding produces the hallmarks of an age-related EM deficit: normal semantic retrieval at encoding, reduced subsequent episodic recognition accuracy, free recall, and the LPEM. Finally, we show that the reduced LPEM in young adults is associated with “additional” brain activity over similar brain areas as those activated when older adults show deficient retrieval. Hence, rather than supporting the compensation hypothesis, these data are more consistent with the scaffolding hypothesis, in which the recruitment of additional cognitive processes is an adaptive response across the life span in the face of momentary increases in task demand due to poorly-encoded episodic memories.

Synesthetic Binding and the Reactivation Model of Memory

2017 ◽  
Author(s):  
Berit Brogaard
Keyword(s):  
Sensory Neurons ◽  
Memory Retrieval ◽  
Brain Activity ◽  
Receptive Fields ◽  
Memory Model ◽  
Multisensory Perception ◽  
Feedback Mechanisms

Despite the recent surge in research on, and interest in, synesthesia, the mechanism underlying this condition is still unknown. Feedforward mechanisms involving overlapping receptive fields of sensory neurons as well as feedback mechanisms involving a lack of signal disinhibition have been proposed. Here I show that a broad range of studies of developmental synesthesia indicate that the mechanism underlying the phenomenon may in some cases involve the reinstatement of brain activity in sensory or cognitive streams in a way that is similar to what happens during memory retrieval of semantically associated items. In the chapter’s final sections I look at the relevance of synesthesia research, given the memory model, to our understanding of multisensory perception and common mapping patterns.

scholarly journals Age differences in brain activity related to unsuccessful declarative memory retrieval

2015 ◽  
Vol 1612 ◽  
pp. 30-47 ◽  
Author(s):  
Cheryl L. Grady ◽  
Marie St-Laurent ◽  
Hana Burianová
Keyword(s):  
Age Differences ◽  
Memory Retrieval ◽  
Declarative Memory ◽  
Brain Activity

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

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.

Sign in / Sign up

Export Citation Format

Share Document