The anatomy of cognitive impairment in amyotrophic lateral sclerosis: More than frontal lobe dysfunction

TY - JOUR

T1 - The anatomy of cognitive impairment in amyotrophic lateral sclerosis: More than frontal lobe dysfunction

AU - Tsermentseli, Stella

AU - Leigh, P. Nigel

AU - Goldstein, Laura H.

PY - 2012/2

Y1 - 2012/2

N2 - Cognitive and behavioural impairments accompanying amyotrophic lateral sclerosis (ALS) have been reported since the early 20th century. Typically, these changes can be associated with a dysexecutive syndrome or manifest as a frontotemporal dementia (FTD). Although the nature of specific frontotemporal dysfunction in ALS remains to be refined, as with the clinical presentation, there is likely to be significant heterogeneity. This article will review the current state of knowledge regarding the neuropathological and neuroanatomical basis for cognitive dysfunction in ALS. Neuropathological findings suggest that ALS does not selectively affect the frontotemporal network but rather is part of a broad clinicopathological spectrum now known as TAR-DNA binding protein (TDP)-43 proteinopathies. Functional neuroimaging has supported neuropsychological findings of frontotemporal dysfunction but has also implied the involvement of somatosensory areas. Structural neuroimaging has not been able to establish a specific hypothesis of extra-motor cortical atrophy beyond the combination of various frontal, temporal and limbic areas. The finding of reduction in the integrity of white matter in the frontal, temporal and parietal lobes including long association fibers suggests that subcortical involvement may underlie both cognitive and functional changes in ALS. Future perspectives for further investigations are highlighted. (C) 2011 Elsevier Srl. All rights reserved.

AB - Cognitive and behavioural impairments accompanying amyotrophic lateral sclerosis (ALS) have been reported since the early 20th century. Typically, these changes can be associated with a dysexecutive syndrome or manifest as a frontotemporal dementia (FTD). Although the nature of specific frontotemporal dysfunction in ALS remains to be refined, as with the clinical presentation, there is likely to be significant heterogeneity. This article will review the current state of knowledge regarding the neuropathological and neuroanatomical basis for cognitive dysfunction in ALS. Neuropathological findings suggest that ALS does not selectively affect the frontotemporal network but rather is part of a broad clinicopathological spectrum now known as TAR-DNA binding protein (TDP)-43 proteinopathies. Functional neuroimaging has supported neuropsychological findings of frontotemporal dysfunction but has also implied the involvement of somatosensory areas. Structural neuroimaging has not been able to establish a specific hypothesis of extra-motor cortical atrophy beyond the combination of various frontal, temporal and limbic areas. The finding of reduction in the integrity of white matter in the frontal, temporal and parietal lobes including long association fibers suggests that subcortical involvement may underlie both cognitive and functional changes in ALS. Future perspectives for further investigations are highlighted. (C) 2011 Elsevier Srl. All rights reserved.

U2 - 10.1016/j.cortex.2011.02.004

DO - 10.1016/j.cortex.2011.02.004

M3 - Literature review

SN - 1973-8102

VL - 48

SP - 166

EP - 182

JO - Cortex

JF - Cortex

IS - 2

ER -