Autonoetic consciousness in Alzheimer's disease: neuropsychological and PET findings using an episodic learning and recognition task.
Géraldine Rauchs, Pascale Piolino, Florence Mezenge, Brigitte Landeau, Catherine Lalevée, Alice Pélerin, Fausto Viader, Vincent de la Sayette, Francis Eustache, Béatrice Desgranges
Neurobiology of Aging September 2007 DOI: 10.1016/j.neurobiolaging.2006.06.005 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational correlational study Peer reviewed |
|---|---|
| Population | Patients with mild Alzheimer's disease and healthy controls |
| Measures | Remember/Know (R/K) paradigm, FDG-PET |
| Key findings | Alzheimer's patients produced fewer Remember responses (autonoetic consciousness) and more Know responses (noetic consciousness) than healthy controls. Remember responses correlated with metabolism in frontal areas bilaterally, while Know responses correlated mainly with metabolism in the left parahippocampal gyrus and lateral temporal cortex. The authors conclude that recollection is impaired in Alzheimer's disease, recognition relies more on familiarity than in controls, and episodic memory impairment is mainly subserved by frontal and hippocampal dysfunction. |
Abstract
This study aims to map in patients with mild Alzheimer's disease (AD) the correlations between resting-state brain glucose utilization measured by FDG-PET and scores reflecting autonoetic consciousness in an episodic learning and recognition task. Autonoetic consciousness, that gives a subject the conscious feeling to mentally travelling back in time to relive an event, was assessed using the Remember/Know (R/K) paradigm. AD patients provided less R responses (reflecting autonoetic consciousness) and more K ones (indicating the involvement of noetic consciousness) than healthy controls. Correct recognitions associated with a R response correlated with the metabolism of frontal areas bilaterally whereas those associated with a K response mainly correlated with the metabolism of left parahippocampal gyrus and lateral temporal cortex. These data show that recollection is impaired in AD and recognition is more based on a feeling of familiarity than in controls. In addition, the findings of our correlative approach indicate that the impairment of episodic memory is mainly subserved by the dysfunction of frontal areas and of the hippocampal region.