Medial thalamic stroke and its impact on familiarity and recollection
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France; CHU Toulouse Purpan, Neurology department, Toulouse, France, France
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France, France
- CHU Toulouse Purpan, Neurology department, Toulouse, France, France
- Department of Diagnostic and Therapeutic Neuroimaging, University of Bordeaux Victor Segalen, Bordeaux University Hospital, France, France
- Brain and Cognition Research Centre (CerCo), CNRS, University of Toulouse Paul Sabatier, Toulouse, France, France
Abstract
Models of recognition memory have postulated that the mammillo-thalamic tract (MTT) / anterior thalamic nucleus (AN) complex would be critical for recollection while the Mediodorsal nucleus (MD) of the thalamus would support familiarity and indirectly also be involved in recollection (Aggleton et al., 2011). 12 patients with left thalamic stroke underwent a neuropsychological assessment, three verbal recognition memory tasks assessing familiarity and recollection each using different procedures and a high-resolution structural MRI. Patients showed poor recollection on all three tasks. In contrast, familiarity was spared in each task. No patient had significant AN lesions. Critically, a subset of 5 patients had lesions of the MD without lesions of the MTT. They also showed impaired recollection but preserved familiarity. Recollection is therefore impaired following MD damage, but familiarity is not. This suggests that models of familiarity, which assign a critical role to the MD, should be reappraised.
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Funding
Toulouse teaching hospital dedicated grant. (Local funding hospital grant)
- Jérémie Pariente
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All participants provided written informed consent in accordance with the declaration of Helsinki to take part in this study, which was approved by the local institutional review board (Comité de Protection des Personnes Sud-Ouest et Outre-Mer no. 2-11-04).
Copyright
© 2017, Danet et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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