Understanding the role of configural processing in face emotion recognition in Parkinson’s disease

This investigation examined whether impairment in configural processing could explain deficits in face emotion recognition in people with Parkinson’s disease (PD). Stimuli from the Radboud Faces Database were used to compare recognition of four negative emotion expressions by older adults with PD (n = 16) and matched controls (n = 17). Participants were tasked with categorizing emotional expressions from upright and inverted whole faces and facial composites; it is difficult to derive configural information from these two types of stimuli so featural processing should play a larger than usual role in accurate recognition of emotional expressions. We found that the PD group were impaired relative to controls in recognizing anger, disgust and fearful expressions in upright faces. Then, consistent with a configural processing deficit, participants with PD showed no composite effect when attempting to identify facial expressions of anger, disgust and fear. A face inversion effect, however, was observed in the performance of all participants in both the whole faces and facial composites tasks. These findings can be explained in terms of a configural processing deficit if it is assumed that the disruption caused by facial composites was specific to configural processing, whereas inversion reduced performance by making it difficult to derive both featural and configural information from faces.     

Tool use in left brain damage and Alzheimer's disease: What about function and manipulation knowledge?

Tool use disorders are usually associated with difficulties in retrieving function and manipulation knowledge. Here, we investigate tool use (Real Tool Use, RTU), function (Functional Association, FA) and manipulation knowledge (Gesture Recognition, GR) in 17 left‐brain‐damaged (LBD) patients and 14 AD patients (Alzheimer disease). LBD group exhibited predicted deficit on RTU but not on FA and GR while AD patients showed deficits on GR and FA with preserved tool use skills. These findings question the role played by function and manipulation knowledge in actual tool use.     

The Portuguese version of Addenbrooke’s Cognitive Examination–Revised (ACE-R) in the diagnosis of subcortical vascular dementia and Alzheimer’s disease

The aim of this study was to investigate the accuracy of the Portuguese version of Addenbrooke’s Cognitive Examination–Revised (ACE-R) in detecting and differentiating early stage subcortical vascular dementia (SVD) from early stage Alzheimer’s disease (AD). Ninety-two subjects (18 SVD patients, 36 AD patients, and 38 healthy controls) were assessed using the ACE-R. Between-group’s differences were evaluated using the Quade’s rank analysis of covariance. The diagnostic accuracy and discriminatory ability of the ACE-R were examined via receiver operating characteristic (ROC) analysis. The ACE-R was able to successfully discriminate between patients and healthy subjects. The mean ACE-R total scores differed between SVD and AD patients; there were also significant differences in attention and orientation and in memory measures between the groups. An optimal cut-off of 72/73 was found for the detection of AD (sensitivity: 97%; specificity: 92%) and SVD (sensitivity: 100%; specificity: 92%).