CBF gradient changes elicited by visual stimulation and visual memory tasks

Introduction: The development of rapid and reliable neural measures of memory is an important goal of cognitive neuroscience research and clinical practice. Fast Periodic Visual Stimulation (FPVS) is a recently developed electroencephalography (EEG) method that involves presenting a mix of novel and previously-learnt stimuli at a fast rate. Recent work has shown that implicit recognition memory can be measured using FPVS, however the role of repetition priming remains unclear. Here, we attempted to separate out the effects of recognition memory and repetition priming by manipulating the degree of repetition of the stimuli to be remembered.Method: Twenty-two participants with a mean age of 20.8 (±4.3) yrs completed an FPVS-oddball paradigm with a varying number of repetitions of the oddball stimuli, ranging from repetition only (pure repetition) to no repetition (pure recognition). In addition to the EEG task, participants completed a behavioural recognition task and visual memory subtests from the Wechsler Memory Scale – 4th edition (WMS-IV). Results: An oddball memory response was observed in all four experimental conditions (pure repetition to pure recognition) compared to the control condition (no oddball stimuli). The oddball memory response was largest in the pure repetition condition and smaller, but still significant, in conditions with less/no oddball repetition (e.g. pure recognition). Behavioural recognition performance was at ceiling, suggesting that all images were encoded successfully. There was no correlation with either behavioural memory performance or WMS-IV scores, suggesting the FPVS-oddball paradigm captures different memory processes than behavioural measures.Conclusion: Repetition priming significantly modulates the FPVS recognition memory response, however recognition is still detectable even in the total absence of repetition priming. The FPVS-oddball paradigm could potentially be developed into an objective and easy-to-administer memory assessment tool.

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Frontal Eye Field Sends Delay Activity Related to Movement, Memory, and Vision to the Superior Colliculus

Journal of Neurophysiology ◽

10.1152/jn.2001.85.4.1673 ◽

2001 ◽

Vol 85 (4) ◽

pp. 1673-1685 ◽

Cited By ~ 105

Author(s):

Marc A. Sommer ◽

Robert H. Wurtz

Keyword(s):

Prefrontal Cortex ◽

Superior Colliculus ◽

Visual Memory ◽

Target Location ◽

Visual Stimulation ◽

Visual Space ◽

Frontal Eye Field ◽

Visual Response ◽

Eye Field ◽

Output Neurons

Many neurons within prefrontal cortex exhibit a tonic discharge between visual stimulation and motor response. This delay activity may contribute to movement, memory, and vision. We studied delay activity sent from the frontal eye field (FEF) in prefrontal cortex to the superior colliculus (SC). We evaluated whether this efferent delay activity was related to movement, memory, or vision, to establish its possible functions. Using antidromic stimulation, we identified 66 FEF neurons projecting to the SC and we recorded from them while monkeys performed a Go/Nogo task. Early in every trial, a monkey was instructed as to whether it would have to make a saccade (Go) or not (Nogo) to a target location, which permitted identification of delay activity related to movement. In half of the trials (memory trials), the target disappeared, which permitted identification of delay activity related to memory. In the remaining trials (visual trials), the target remained visible, which permitted identification of delay activity related to vision. We found that 77% (51/66) of the FEF output neurons had delay activity. In 53% (27/51) of these neurons, delay activity was modulated by Go/Nogo instructions. The modulation preceded saccades made into only part of the visual field, indicating that the modulation was movement-related. In some neurons, delay activity was modulated by Go/Nogo instructions in both memory and visual trials and seemed to represent where to move in general. In other neurons, delay activity was modulated by Go/Nogo instructions only in memory trials, which suggested that it was a correlate of working memory, or only in visual trials, which suggested that it was a correlate of visual attention. In 47% (24/51) of FEF output neurons, delay activity was unaffected by Go/Nogo instructions, which indicated that the activity was related to the visual stimulus. In some of these neurons, delay activity occurred in both memory and visual trials and seemed to represent a coordinate in visual space. In others, delay activity occurred only in memory trials and seemed to represent transient visual memory. In the remainder, delay activity occurred only in visual trials and seemed to be a tonic visual response. In conclusion, the FEF sends diverse delay activity signals related to movement, memory, and vision to the SC, where the signals may be used for saccade generation. Downstream transmission of various delay activity signals may be an important, general way in which the prefrontal cortex contributes to the control of movement.

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Effects of Rhythmic and Simple Auditory Stimulations on Learning the Timing of Sequential Motor Task in Children With DCD

Journal of Exercise Science and Medicine ◽

10.32598/jesm.12.1.3 ◽

2020 ◽

Vol 12 (1) ◽

pp. 157-166

Author(s):

Ahmad Dehnavi ◽

◽

Alireza Saberi Kakhaki ◽

Hamidreza Taheri Torbati ◽

Mohammadreza Shahabi Kaeb ◽

...

Keyword(s):

Visual Memory ◽

Developmental Coordination Disorder ◽

Visual Stimulation ◽

Motor Task ◽

Control Group ◽

Spatial Awareness ◽

Significant Difference ◽

Movement Assessment ◽

Group 2 ◽

Coordination Disorder

Introduction: Children and adolescents with Developmental Coordination Disorder (DCD) usually fail to understand spatial awareness and motor timing. The present study assessed Rhythmic Auditory Stimulations (RAS) and Simple Auditory Stimulations (SAS) to facilitate the learning of timing in sequential motor task and recorded the results of their relative and absolute timing errors. Materials and Methods: 56 male students aged 9-12 years with DCD in Neyshabur city were selected by diagnosing with the following tools: Teacher Motor Inventory, Parental Developmental Coordination Disorder Questionnaire, Movement Assessment Battery for Children-Second (MABC-2 movement test), spatial-visual memory assessment, intelligence assessment, RT test, and biopsychological health status evaluation. Then, they were divided into RAS, SAS, control group 1 (visual), and control group 2. Moreover, a pretest score was performed. Next, the training protocol was presented in 10 blocks of 5 attempts and the acquisition test was performed. Finally, the retention and transfer tests were performed after 48 hours and 10 minutes, respectively. Results: Based on the obtained results, a significant difference was observed between the visual stimulation group and the RAS and SAS groups in relative and absolute timing components (P≤0.05). However, no significant difference was reported between the rhythmic, SAS, and visual-auditory stimulation groups in relative and absolute timing variables (P˃0.05). Conclusion: Finally, no significant difference was observed between the RAS and simple stimulations although the graphs displayed the effect of the first stimulation more than that of the second one.

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Differential Generation of Saccade, Fixation, and Image-Onset Event-Related Potentials in the Human Mesial Temporal Lobe

Cerebral Cortex ◽

10.1093/cercor/bhaa132 ◽

2020 ◽

Vol 30 (10) ◽

pp. 5502-5516

Author(s):

Chaim N Katz ◽

Kramay Patel ◽

Omid Talakoub ◽

David Groppe ◽

Kari Hoffman ◽

...

Keyword(s):

Eye Movements ◽

Temporal Lobe ◽

Visual Information ◽

Visual Memory ◽

Visual Stimulation ◽

Low Frequency ◽

Event Related Potentials ◽

Saccade Onset ◽

Related Potentials ◽

Mesial Temporal Lobe

Abstract Event-related potentials (ERPs) are a commonly used electrophysiological signature for studying mesial temporal lobe (MTL) function during visual memory tasks. The ERPs associated with the onset of visual stimuli (image-onset) and eye movements (saccades and fixations) provide insights into the mechanisms of their generation. We hypothesized that since eye movements and image-onset provide MTL structures with salient visual information, perhaps they both engage similar neural mechanisms. To explore this question, we used intracranial electroencephalographic data from the MTLs of 11 patients with medically refractory epilepsy who participated in a visual search task. We characterized the electrophysiological responses of MTL structures to saccades, fixations, and image-onset. We demonstrated that the image-onset response is an evoked/additive response with a low-frequency power increase. In contrast, ERPs following eye movements appeared to arise from phase resetting of higher frequencies than the image-onset ERP. Intriguingly, this reset was associated with saccade onset and not termination (fixation), suggesting it is likely the MTL response to a corollary discharge, rather than a response to visual stimulation. We discuss the distinct mechanistic underpinnings of these responses which shed light on the underlying neural circuitry involved in visual memory processing.

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Differential generation of saccade, fixation and image onset event-related potentials in the human mesial temporal lobe

10.1101/442855 ◽

2018 ◽

Cited By ~ 2

Author(s):

Chaim N. Katz ◽

Kramay Patel ◽

Omid Talakoub ◽

David Groppe ◽

Kari Hoffman ◽

...

Keyword(s):

Eye Movements ◽

Temporal Lobe ◽

Visual Information ◽

Visual Memory ◽

Visual Stimulation ◽

Event Related Potentials ◽

Saccade Onset ◽

Related Potentials ◽

Mesial Temporal Lobe ◽

Onset Response

The electrophysiological signatures of encoding and retrieval recorded from mesial temporal lobe (MTL) structures are observed as event related potentials (ERPs) during visual memory tasks. The waveforms of the ERPs associated with the onset of visual stimuli (image-onset) and eye movements (saccades and fixations) provide insights into the mechanisms of their generation. We hypothesized that since eye movements and image-onset (common methods of stimulus presentation when testing memory) provide MTL structures with salient visual information, that perhaps they both engage similar neural mechanisms. To explore this question, we used intracranial electroencephalographic (iEEG) data from the MTLs of 11 patients with medically refractory epilepsy who participated in a visual search task. We sought to characterize electrophysiological responses of MTL structures to saccades, fixations and image onset. We demonstrate that the image-onset response is an evoked/additive response with a low-frequency power increase and post-stimulus phase clustering. In contrast, ERPs following eye movements appeared to arise from phase resetting of higher frequencies than the image onset ERP. Intriguingly, this reset was associated with saccade onset and not saccade termination (fixation), suggesting it is likely the MTL response to a corollary discharge, rather than a response to visual stimulation - in stark contrast to the image onset response. The distinct mechanistic underpinnings of these two ERP may help guide future development of visual memory tasks.

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