The closing-in phenomenon in constructional tasks in dementia and mild cognitive impairment

Closing-in (CI) consists in copying drawings near to (near-CI) or superimposed on (adherent-CI) the model and often occurs in dementia and mild cognitive impairment (MCI). We assessed whether a visuo-constructional task not requiring a grapho-motor response is sensitive to identify CI in Alzheimer's disease (AD), fronto-temporal dementia (FTD), vascular dementia (VD), and MCI.

We enrolled a sample of 162 patients with dementia (AD, FTD, or VD), 66 individuals with MCI, and 20 healthy adults (HAs) who completed a neuropsychological assessment and the Stick Design test that requires arranging matches for reproducing geometrical figures.

CI in the Stick test was slightly (but not significantly) more frequent than that observed in the copying drawing task. CI frequency on both tests was high and similar in AD and FTD and lower in VD and MCI. On both tests, near-CI was the most common error in VD and MCI, whereas adherent-CI prevailed in patients with AD; a similar percentage of near-CI and adherent-CI was observed in FTD. Last, in the participants with dementia and MCI, the number of CIs was significantly correlated with an index of control and executive functions but not with spatial short-term memory.

CI occurs with the same frequency in AD, VD, and FTD, but the prevalent type of CI varies across syndromes. The Stick Design test is a useful task to assess CI and its specific forms in dementia and MCI. (PsycINFO Database Record (c) 2020 APA, all rights reserved).