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Neural correlates of attentional and mnemonic processing in event-based prospective memory.

Knight JB, Ethridge LE, Marsh RL, Clementz BA - Front Hum Neurosci (2010)

Bottom Line: Specifically, the neural substrates of monitoring for an event-based cue were examined, as well as those perhaps associated with the cognitive processes supporting detection of cues and fulfillment of intentions.Analysis of the event-related potentials (ERP) revealed visual attentional modulations at 140 and 220 ms post-stimulus associated with preparatory attentional processes.Our results suggest preparatory attention may operate by selectively modulating processing of features related to a previously formed event-based intention, as well as provide further evidence for the proposal that dissociable component processes support the fulfillment of delayed intentions.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Georgia Athens, GA, USA.

ABSTRACT
Prospective memory (PM), or memory for realizing delayed intentions, was examined with an event-based paradigm while simultaneously measuring neural activity with high-density EEG recordings. Specifically, the neural substrates of monitoring for an event-based cue were examined, as well as those perhaps associated with the cognitive processes supporting detection of cues and fulfillment of intentions. Participants engaged in a baseline lexical decision task (LDT), followed by a LDT with an embedded PM component. Event-based cues were constituted by color and lexicality (red words). Behavioral data provided evidence that monitoring, or preparatory attentional processes, were used to detect cues. Analysis of the event-related potentials (ERP) revealed visual attentional modulations at 140 and 220 ms post-stimulus associated with preparatory attentional processes. In addition, ERP components at 220, 350, and 400 ms post-stimulus were enhanced for intention-related items. Our results suggest preparatory attention may operate by selectively modulating processing of features related to a previously formed event-based intention, as well as provide further evidence for the proposal that dissociable component processes support the fulfillment of delayed intentions.

No MeSH data available.


(A) Grand-averaged ERP waveforms for LDT/PM words/nonwords and Cues/Lures for the 220 ms component (marked with black arrow).  Occipital-parietal ERP waveforms were derived by averaging sensors from the significant cluster that resulted from the planned contrast. Negative is plotted up. (B) A topographical voltage distribution averaged within time windows centered on the peak latency of the 220 ms component. Positive isopotential lines are in red, negative isopotential lines are in blue. Isopotential line scale is: 0.64 μV/step. Due to similarities in topographic distributions across conditions, they are averaged and presented as one voltage topography. (C) A plot of t-values (absolute value taken) over the head surface indicates the sensor clusters for which there were significant effects between LDT/PM-words versus cues and LDT/PM-nonwords versus lures at 220 ms post-stimulus. The two effects are presented together due to the high similarity between the two comparisons, suggesting red PM-items were preferentially processed at this time point. The critical t-value (t = 2.3281) is marked on the scale.
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Figure 3: (A) Grand-averaged ERP waveforms for LDT/PM words/nonwords and Cues/Lures for the 220 ms component (marked with black arrow). Occipital-parietal ERP waveforms were derived by averaging sensors from the significant cluster that resulted from the planned contrast. Negative is plotted up. (B) A topographical voltage distribution averaged within time windows centered on the peak latency of the 220 ms component. Positive isopotential lines are in red, negative isopotential lines are in blue. Isopotential line scale is: 0.64 μV/step. Due to similarities in topographic distributions across conditions, they are averaged and presented as one voltage topography. (C) A plot of t-values (absolute value taken) over the head surface indicates the sensor clusters for which there were significant effects between LDT/PM-words versus cues and LDT/PM-nonwords versus lures at 220 ms post-stimulus. The two effects are presented together due to the high similarity between the two comparisons, suggesting red PM-items were preferentially processed at this time point. The critical t-value (t = 2.3281) is marked on the scale.

Mentions: At 140 ms, neither the PM-cues versus (PM-words + LDT-words/2) nor the PM-lures versus (PM-nonwords + LDT-nonwords/2) comparisons differed significantly. At 220 ms, however, both of these comparisons revealed significant sensor clusters (see Figure 3). The pattern of these significant relationships were highly similar between the two comparisons (r = 0.92 for the between-conditions t-value distributions over all 211 sensors), indicating that red items, regardless of their status (cue, lure), were processed differently than nonred items at this time point. In addition, the topographic distributions of voltages were highly similar between red and nonred items for the 220 ms ERP peak (r = 0.97 for the between-conditions voltage distributions over all 211 sensors), but red items (both PM-cues and PM-lures) had significantly higher voltages over occipital-parietal regions than did nonred items (M cluster diff = −0.39 μV, SE = 0.11), t(11) = −3.43, p = 0.006, (see Figure 3). An additional indication that red items were processed differently from non-red items was the ERP peak at 350 ms that was present for only PM-cues and PM-lures (see Figure 4). There were no significant differences, however, between cues and lures at this peak, and the spatial distribution of their neural activations were highly similar (r = 0.96 for the between-conditions voltage distributions over all 211 sensors).


Neural correlates of attentional and mnemonic processing in event-based prospective memory.

Knight JB, Ethridge LE, Marsh RL, Clementz BA - Front Hum Neurosci (2010)

(A) Grand-averaged ERP waveforms for LDT/PM words/nonwords and Cues/Lures for the 220 ms component (marked with black arrow).  Occipital-parietal ERP waveforms were derived by averaging sensors from the significant cluster that resulted from the planned contrast. Negative is plotted up. (B) A topographical voltage distribution averaged within time windows centered on the peak latency of the 220 ms component. Positive isopotential lines are in red, negative isopotential lines are in blue. Isopotential line scale is: 0.64 μV/step. Due to similarities in topographic distributions across conditions, they are averaged and presented as one voltage topography. (C) A plot of t-values (absolute value taken) over the head surface indicates the sensor clusters for which there were significant effects between LDT/PM-words versus cues and LDT/PM-nonwords versus lures at 220 ms post-stimulus. The two effects are presented together due to the high similarity between the two comparisons, suggesting red PM-items were preferentially processed at this time point. The critical t-value (t = 2.3281) is marked on the scale.
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Related In: Results  -  Collection

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Show All Figures
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Figure 3: (A) Grand-averaged ERP waveforms for LDT/PM words/nonwords and Cues/Lures for the 220 ms component (marked with black arrow). Occipital-parietal ERP waveforms were derived by averaging sensors from the significant cluster that resulted from the planned contrast. Negative is plotted up. (B) A topographical voltage distribution averaged within time windows centered on the peak latency of the 220 ms component. Positive isopotential lines are in red, negative isopotential lines are in blue. Isopotential line scale is: 0.64 μV/step. Due to similarities in topographic distributions across conditions, they are averaged and presented as one voltage topography. (C) A plot of t-values (absolute value taken) over the head surface indicates the sensor clusters for which there were significant effects between LDT/PM-words versus cues and LDT/PM-nonwords versus lures at 220 ms post-stimulus. The two effects are presented together due to the high similarity between the two comparisons, suggesting red PM-items were preferentially processed at this time point. The critical t-value (t = 2.3281) is marked on the scale.
Mentions: At 140 ms, neither the PM-cues versus (PM-words + LDT-words/2) nor the PM-lures versus (PM-nonwords + LDT-nonwords/2) comparisons differed significantly. At 220 ms, however, both of these comparisons revealed significant sensor clusters (see Figure 3). The pattern of these significant relationships were highly similar between the two comparisons (r = 0.92 for the between-conditions t-value distributions over all 211 sensors), indicating that red items, regardless of their status (cue, lure), were processed differently than nonred items at this time point. In addition, the topographic distributions of voltages were highly similar between red and nonred items for the 220 ms ERP peak (r = 0.97 for the between-conditions voltage distributions over all 211 sensors), but red items (both PM-cues and PM-lures) had significantly higher voltages over occipital-parietal regions than did nonred items (M cluster diff = −0.39 μV, SE = 0.11), t(11) = −3.43, p = 0.006, (see Figure 3). An additional indication that red items were processed differently from non-red items was the ERP peak at 350 ms that was present for only PM-cues and PM-lures (see Figure 4). There were no significant differences, however, between cues and lures at this peak, and the spatial distribution of their neural activations were highly similar (r = 0.96 for the between-conditions voltage distributions over all 211 sensors).

Bottom Line: Specifically, the neural substrates of monitoring for an event-based cue were examined, as well as those perhaps associated with the cognitive processes supporting detection of cues and fulfillment of intentions.Analysis of the event-related potentials (ERP) revealed visual attentional modulations at 140 and 220 ms post-stimulus associated with preparatory attentional processes.Our results suggest preparatory attention may operate by selectively modulating processing of features related to a previously formed event-based intention, as well as provide further evidence for the proposal that dissociable component processes support the fulfillment of delayed intentions.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Georgia Athens, GA, USA.

ABSTRACT
Prospective memory (PM), or memory for realizing delayed intentions, was examined with an event-based paradigm while simultaneously measuring neural activity with high-density EEG recordings. Specifically, the neural substrates of monitoring for an event-based cue were examined, as well as those perhaps associated with the cognitive processes supporting detection of cues and fulfillment of intentions. Participants engaged in a baseline lexical decision task (LDT), followed by a LDT with an embedded PM component. Event-based cues were constituted by color and lexicality (red words). Behavioral data provided evidence that monitoring, or preparatory attentional processes, were used to detect cues. Analysis of the event-related potentials (ERP) revealed visual attentional modulations at 140 and 220 ms post-stimulus associated with preparatory attentional processes. In addition, ERP components at 220, 350, and 400 ms post-stimulus were enhanced for intention-related items. Our results suggest preparatory attention may operate by selectively modulating processing of features related to a previously formed event-based intention, as well as provide further evidence for the proposal that dissociable component processes support the fulfillment of delayed intentions.

No MeSH data available.