Cognitive profile of patients with rotated drawing at copy or recall: a controlled group study.

When copying or recalling a figure from memory, some patient with dementia or focal brain lesions may rotate the drawing through ±90° or 180°. We have tried to clarify the nature of this phenomenon by investigating the cognitive profile of 22 patients who rotated the copy of the Rey-Osterrieth Complex Figure and 27 who rotated (only) the recall, and two control groups of cases with the same neuropsychiatric diagnoses, but no misorientation deficit. Brain MRI and FDG-PET images were also analysed. Predictor of rotation at the copy versus rotation at the recall was visuospatial impairment as measured by the copy of the Rey Figure; predictors of rotation at the copy versus no rotation were, again, visuospatial deficits, in addition to an abnormal performance at the task of selective attention. No specific profile of cognitive impairment distinguished patients with and without rotation at the recall. Disproportionate temporo-parieto-occipital atrophy or hypometabolism were evident in cases with misorientation of the copy, while predominant frontal abnormalities were found in cases of rotated recall. Based on these findings, rotated drawing at the copy is interpreted as a dorsal visual stream deficit, whose occurrence is more probable when attentional control is impaired. Rotation at recall seems to have a distinct, more anterior, neural substrate, but its dysexecutive nature has yet to be demonstrated.

The applause sign in cortical and cortical-subcortical dementia.

The "applause sign" is a motor perseveration described in focal and neurodegenerative disorders and characterized by fronto-subcortical dysfunction. Most previous formal investigations focused on Parkinson's disease or progressive supranuclear palsy. We assessed the prevalence of the applause sign in patients affected by Alzheimer's disease (AD), Lewy body dementia (LBD), corticobasal syndrome (CBS), and posterior cortical atrophy (PCA), with the aim to verify its contribution to the differential diagnosis. We enrolled 20 patients with AD, 20 with LBD, 16 with CBS, and ten with PCA, and 30 healthy controls. The three clap test (TCT) was used to elicit the applause sign, and was scored by raters blinded to the diagnosis. Correlation with motor (extrapyramidal) and cognitive measures was also performed. A maximum 40 % prevalence of a positive applause sign was found in the two parkinsonian syndromes, which could be discriminated from the two cortical groups with a positive predictive value of 82 % and a negative predictive value of 55 %. According to our findings, a diagnosis of LBD or CBS, rather than of AD or PCA, is highly probable in the presence of an abnormal TCP, but cannot be ruled out based on a negative result. No relevant correlates emerged that could clarify the origin and nature of the applause sign.

A retrospective survey on rotated drawing in persons with mild cognitive impairment or degenerative dementia.

Rotation of drawings has been described in focal brain lesions, at copy when the dorsal visual stream is involved, at recall in patients with memory or frontal dysfunction. In the present study Rey-Osterrieth Complex Figure performance was reviewed in 445 consecutive patients with mild cognitive impairment or degenerative dementia; a smaller sample (n = 243) had also performed the recall trial. Rotation was present in 19 cases overall: at copy in 11, at recall in 7, and at recall on a first assessment and at copy on retest in 1 last patient. Rotation at copy was often associated with neuropsychological and metabolic imaging evidence of parietal dysfunction, supporting previous evidence that rotation at copy might be due to an impairment of object perception processes within the dorsal visual stream. Rotation at recall seemed to be related predominantly to executive deficits, but no specific hypothesis on its cognitive origin can be advanced based on the present data.