Medial Temporal Lobe Involvement in an Implicit Memory Task: Evidence of Collaborating Implicit and Explicit Memory Systems from fMRI and Alzheimer's Disease Export

@article{citeulike:3313762, abstract = {We used a prototype extraction task to assess implicit learning of a meaningful novel visual category. Cortical activation was monitored in young adults with functional magnetic resonance imaging. We observed occipital deactivation at test consistent with perceptually based implicit learning, and lateral temporal cortex deactivation reflecting implicit acquisition of the category's semantic nature. Medial temporal lobe (MTL) activation during exposure and test suggested involvement of explicit memory as well. Behavioral performance of Alzheimer's disease (AD) patients and healthy seniors was also assessed, and AD performance was correlated with gray matter volume using voxel-based morphometry. AD patients showed learning, consistent with preserved implicit memory, and confirming that AD patients' implicit memory is not limited to abstract patterns. However, patients were somewhat impaired relative to healthy seniors. Occipital and lateral temporal cortical volume correlated with successful AD patient performance, and thus overlapped with young adults' areas of deactivation. Patients' severe MTL atrophy precluded involvement of this region. AD patients thus appear to engage a cortically based implicit memory mechanism, whereas their relative deficit on this task may reflect their MTL disease. These findings suggest that implicit and explicit memory systems collaborate in neurologically intact individuals performing an ostensibly implicit memory task. 10.1093/cercor/bhn043}, author = {Koenig, Phyllis and Smith, Edward E. and Troiani, Vanessa and Anderson, Chivon and Moore, Peachie and Grossman, Murray}, citeulike-article-id = {3313762}, citeulike-linkout-0 = {http://dx.doi.org/10.1093/cercor/bhn043}, citeulike-linkout-1 = {http://cercor.oxfordjournals.org/cgi/content/abstract/18/12/2831}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/18400793}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=18400793}, day = {9}, doi = {10.1093/cercor/bhn043}, journal = {Cereb. Cortex}, keywords = {2008, ad}, month = {April}, pages = {bhn043+}, posted-at = {2008-09-22 09:55:10}, priority = {2}, title = {Medial Temporal Lobe Involvement in an Implicit Memory Task: Evidence of Collaborating Implicit and Explicit Memory Systems from fMRI and Alzheimer's Disease}, url = {http://dx.doi.org/10.1093/cercor/bhn043}, year = {2008} }

TY - JOUR ID - citeulike:3313762 L3 - citeulike-article-id:3313762 N2 - We used a prototype extraction task to assess implicit learning of a meaningful novel visual category. Cortical activation was monitored in young adults with functional magnetic resonance imaging. We observed occipital deactivation at test consistent with perceptually based implicit learning, and lateral temporal cortex deactivation reflecting implicit acquisition of the category's semantic nature. Medial temporal lobe (MTL) activation during exposure and test suggested involvement of explicit memory as well. Behavioral performance of Alzheimer's disease (AD) patients and healthy seniors was also assessed, and AD performance was correlated with gray matter volume using voxel-based morphometry. AD patients showed learning, consistent with preserved implicit memory, and confirming that AD patients' implicit memory is not limited to abstract patterns. However, patients were somewhat impaired relative to healthy seniors. Occipital and lateral temporal cortical volume correlated with successful AD patient performance, and thus overlapped with young adults' areas of deactivation. Patients' severe MTL atrophy precluded involvement of this region. AD patients thus appear to engage a cortically based implicit memory mechanism, whereas their relative deficit on this task may reflect their MTL disease. These findings suggest that implicit and explicit memory systems collaborate in neurologically intact individuals performing an ostensibly implicit memory task. 10.1093/cercor/bhn043 JF - Cereb. Cortex TI - Medial Temporal Lobe Involvement in an Implicit Memory Task: Evidence of Collaborating Implicit and Explicit Memory Systems from fMRI and Alzheimer's Disease SP - bhn043 KW - 2008 KW - ad AU - Koenig, Phyllis AU - Smith, Edward AU - Troiani, Vanessa AU - Anderson, Chivon AU - Moore, Peachie AU - Grossman, Murray PY - 2008/04/09/ UR - http://dx.doi.org/10.1093/cercor/bhn043 ER -