Executive function deficits in persons with mild cognitive impairment: A study with a Tower of London task

Abstract

This study assessed executive functions in persons with mild cognitive impairment (MCI) using the Tower of London (TOL). A second objective was to study the impact of three types of problem selected according to the presence or absence of a "trigger." A trigger (T) is an incitation to the participant, at the first move, to move a ball to its final position according to the model. A positive trigger (T+) is helpful, while a negative trigger (T-) creates an obstruction. Some problems have no trigger (N). This study includes 81 participants with MCI. After follow-up, one year later, two subgroups were distinguished: (a) 51 (63%) participants did not convert or decline (stable MCI); (b) 30 (37%) participants showed significant decline or progressed to dementia (decliner MCI). Persons with MCI were compared to an older adult group matched with respect to sex, age, and education. For the successes, there was a significant group difference between the three types of problem. The post hoc analysis showed that T+ took significantly less time than N or T-. There were significantly more successes for T+ than N, and these two types of problem had more success than T-. For "total number of moves," there was no significant difference between the groups. In post hoc analysis, T- involved more moves than N or T+. In qualitative analysis, T- MCI decliners produced significantly more rule breakings than the stable MCI and controls. A dysfunction in self-monitoring is a characteristic feature of persons with MCI.

Conscious Attention Defect and Inhibitory Control Deficit in Parkinson’s Disease-Mild Cognitive Impairment: A Comparison Study With Amnestic Mild Cognitive Impairment Multiple Domain

“…PD-MCI patients significantly differed from controls in TOL DX Violation Time subtest, by suggesting a weakening of executive planning efficiency but not as severe as that reported by aMCI+ patients. The results of the aMCI+ group on this subtest is in line whit a previous study that pointed out how MCI decliners show a dysfunction in selfmonitoring/rule-bound control than stable MCI patients and controls (Rainville et al 2012). Total Initiation Time, which is the time from the presentation of a test problem by the examiner to the initiation of the first problem-solving move, is more damaged in aMCI+ than PD-MCI patients accounting for a more pronounced deficit in time assumed for planning accuracy/task analysis on the moves sequence.…”

Neural correlates of cognitive intervention in persons at risk of developing Alzheimer’s disease

“…Functional neuroimaging studies on MCI showed hyper-activation and hypo-activation in prefrontal regions in MCI patients with high and low cognitive functions, respectively (Dannhauser et al, 2005; Yetkin et al, 2006), an observation that suggest a breakdown of executive function network with progression of AD. These data are corroborated by recent evidence that showed impairments in EF even in early stages of AD (Rainville et al, 2012; Clément et al, 2013). These data suggest that including training components focused on EF in the practicum is necessary to restore/normalize the affected structure/function of the prefrontal regions and to further facilitate the recovery of the medial temporal regions.…”

O2‐07‐03: Patterns of Cognitive Decline Prior to Dementia in Persons With Mild Cognitive Impairment

“…One other crucial difference between the two studies is that we differentiated nonprogressor from progressor MCI. Some studies have indicated that executive functions and inhibition are more impaired in progressors than in non-progressor MCIs [20,21,43,47] and predictive models that are most sensitive and specific often include executive function measures [11] (for a review, see [37]). Our results support this literature as executive functions were found to differ between non-progressor and progressor MCI and only the latter showed increased impairment.…”