Increased sensitivity to proactive and retroactive interference in amnestic mild cognitive impairment: new insights.
BACKGROUND
Increased sensitivity to proactive (PI) and retroactive (RI) interference has been observed in amnestic mild cognitive impairment (aMCI). PI and RI are often explained as being the result of a response competition mechanism. However, patients with aMCI are supposed to suffer mostly from encoding deficits. We hypothesized that in aMCI interference may occur at encoding and not only at the retrieval stage.


METHODS
We developed an original paradigm enabling PI and RI to be tested with and without response competitors. Eighteen young controls (YC), 16 elderly controls (EC) and 15 aMCI participated in the study.


RESULTS
The YC and EC groups presented interference effects only in conditions that included a direct response competitor. In contrast, aMCI had interference effects in all conditions including the one without response competitor.


CONCLUSIONS
Increased sensitivity to interference in aMCI appears to occur at the encoding/consolidation stage and not only at the retrieval stage, as is the case in healthy subjects. This result is discussed in the context of the associative encoding deficits characterizing aMCI.
Saint-Luc University Hospital, Department of Neurology, Brussels, Belgium. Bernard.Hanseeuw@uclouvain.be
Bernard J
BJ
Hanseeuw
Xavier
X
Seron
Adrian
A
Ivanoiu
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000647:Amnesia / Q000523:psychology*; D001288:Attention; D060825:Cognitive Dysfunction / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory; D009483:Neuropsychological Tests