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FMRI of working memory impairment after recovery from subarachnoid hemorrhage.

Ellmore TM, Rohlffs F, Khursheed F - Front Neurol (2013)

Bottom Line: Behavioral results indicated a subtle but statistically significant impairment relative to healthy subjects in working memory performance accuracy, which was accompanied by relatively increased blood-oxygen level dependent signal in widespread left and right hemisphere cortical areas during periods of encoding, maintenance, and retrieval.We conclude that deficits in verbal working memory following recovery from (SAH) are accompanied by widespread differences in hemodynamic correlates of neural activity.These differences are discussed with respect to the immediate and delayed focal and global brain damage that can occur following (SAH), and the possibility that this damage induces subcortical disconnection and subsequent decreased efficiency in neural processing.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology and Program in Behavioral and Cognitive Neuroscience, The City College of New York , New York, NY , USA.

ABSTRACT
Recovery from aneurysmal subarachnoid hemorrhage (SAH) is often incomplete and accompanied by subtle but persistent cognitive deficits. Previous neuropsychological reports indicate these deficits include most prominently memory impairment, with working memory particularly affected. The neural basis of these memory deficits remains unknown and unexplored by functional magnetic resonance imaging (fMRI). In the present study, patients who experienced (SAH) underwent fMRI during the performance of a verbal working memory paradigm. Behavioral results indicated a subtle but statistically significant impairment relative to healthy subjects in working memory performance accuracy, which was accompanied by relatively increased blood-oxygen level dependent signal in widespread left and right hemisphere cortical areas during periods of encoding, maintenance, and retrieval. Activity increases remained after factoring out inter-individual differences in age and task performance, and included most notably left hemisphere regions associated with phonological loop processing, bilateral sensorimotor regions, and right hemisphere dorsolateral prefrontal cortex. We conclude that deficits in verbal working memory following recovery from (SAH) are accompanied by widespread differences in hemodynamic correlates of neural activity. These differences are discussed with respect to the immediate and delayed focal and global brain damage that can occur following (SAH), and the possibility that this damage induces subcortical disconnection and subsequent decreased efficiency in neural processing.

No MeSH data available.


Related in: MedlinePlus

Subarachnoid hemorrhage patients show working memory task impairment. Compared to controls, SAH patients show significant reductions in working memory task accuracy (A) but no significant differences in speed of choices made during memory trials (B).
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Figure 1: Subarachnoid hemorrhage patients show working memory task impairment. Compared to controls, SAH patients show significant reductions in working memory task accuracy (A) but no significant differences in speed of choices made during memory trials (B).

Mentions: Patients performed significantly worse (percent correct 82.9 vs. 97.5, p < 0.003, Figure 1A) in terms of working memory task accuracy. While the time taken by patients was longer (1204 vs. 1058 ms, Figure 1B) to decide whether the probe stimulus at retrieval was or was not one of the four stimuli previously presented during the encoding period, the difference was not significant (p = 0.42).


FMRI of working memory impairment after recovery from subarachnoid hemorrhage.

Ellmore TM, Rohlffs F, Khursheed F - Front Neurol (2013)

Subarachnoid hemorrhage patients show working memory task impairment. Compared to controls, SAH patients show significant reductions in working memory task accuracy (A) but no significant differences in speed of choices made during memory trials (B).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3818578&req=5

Figure 1: Subarachnoid hemorrhage patients show working memory task impairment. Compared to controls, SAH patients show significant reductions in working memory task accuracy (A) but no significant differences in speed of choices made during memory trials (B).
Mentions: Patients performed significantly worse (percent correct 82.9 vs. 97.5, p < 0.003, Figure 1A) in terms of working memory task accuracy. While the time taken by patients was longer (1204 vs. 1058 ms, Figure 1B) to decide whether the probe stimulus at retrieval was or was not one of the four stimuli previously presented during the encoding period, the difference was not significant (p = 0.42).

Bottom Line: Behavioral results indicated a subtle but statistically significant impairment relative to healthy subjects in working memory performance accuracy, which was accompanied by relatively increased blood-oxygen level dependent signal in widespread left and right hemisphere cortical areas during periods of encoding, maintenance, and retrieval.We conclude that deficits in verbal working memory following recovery from (SAH) are accompanied by widespread differences in hemodynamic correlates of neural activity.These differences are discussed with respect to the immediate and delayed focal and global brain damage that can occur following (SAH), and the possibility that this damage induces subcortical disconnection and subsequent decreased efficiency in neural processing.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology and Program in Behavioral and Cognitive Neuroscience, The City College of New York , New York, NY , USA.

ABSTRACT
Recovery from aneurysmal subarachnoid hemorrhage (SAH) is often incomplete and accompanied by subtle but persistent cognitive deficits. Previous neuropsychological reports indicate these deficits include most prominently memory impairment, with working memory particularly affected. The neural basis of these memory deficits remains unknown and unexplored by functional magnetic resonance imaging (fMRI). In the present study, patients who experienced (SAH) underwent fMRI during the performance of a verbal working memory paradigm. Behavioral results indicated a subtle but statistically significant impairment relative to healthy subjects in working memory performance accuracy, which was accompanied by relatively increased blood-oxygen level dependent signal in widespread left and right hemisphere cortical areas during periods of encoding, maintenance, and retrieval. Activity increases remained after factoring out inter-individual differences in age and task performance, and included most notably left hemisphere regions associated with phonological loop processing, bilateral sensorimotor regions, and right hemisphere dorsolateral prefrontal cortex. We conclude that deficits in verbal working memory following recovery from (SAH) are accompanied by widespread differences in hemodynamic correlates of neural activity. These differences are discussed with respect to the immediate and delayed focal and global brain damage that can occur following (SAH), and the possibility that this damage induces subcortical disconnection and subsequent decreased efficiency in neural processing.

No MeSH data available.


Related in: MedlinePlus