Familiarity for famous faces and names is not equally subtended by the right and left temporal poles. Evidence from an rTMS study.

The aims of the present experiment was to investigate: (a) if transient disruption of neural activity in the right (RTP) or left temporal pole (LTP) can interfere with the development of a familiarity feeling to the presentation of faces/written names of famous/unknown people; and (b) if this interference specifically affects the familiarity for faces after inhibition of the RTP and for names after inhibition of the LTP. Twenty healthy volunteers took part in the study. Repetitive transcranial magnetic stimulation (rTMS) was administered online; it disrupted the neural activity of the right or left TP in concomitance with the presentation of each face and name whose familiarity had to be assessed. Furthermore, in a control group, each participant was submitted to a single experimental session in which rTMS was delivered to the vertex in association with the presentation of faces and written names. Since previous rTMS studies have shown that the temporary inactivation of the right and left TP influences the response latencies, but not the number of correct responses, in this study we took into account both the number of correct responses obtained in different experimental conditions and the corresponding response latencies. A three-way factorial ANOVA carried out on the Response Scores showed only a general effect of the Type of Stimuli, due to better performances on names than on faces. This greater familiarity of names is consistent with previous data reported in the literature. In the three-way factorial ANOVA carried out on the Latency Scores, post-hoc analyses showed an increased latency of responses to faces after right stimulation in Latency Total, Latency on Correct responses and Latency on Unfamiliar faces. None of these results were obtained in the control group. These data suggest that rTMS at the level of the RTP preferentially affects the development of familiarity feelings to the presentation of faces of famous people.

The Multiple Features Target Cancellation (MFTC): an attentional visual conjunction search test. Normative values for the Italian population.

Several studies, showing that attention disorders during encoding reduce later memory performance, have stressed the critical role of attention for the formation of durable memory traces. Accordingly, some studies suggest that attentive disturbances, together with declarative memory defects, can constitute the earliest cognitive disorders in Alzheimer's disease. Therefore, the analysis of these disorders can contribute to identify different forms of dementia and to detect demented patients characterized by a faster cognitive decline. In this study, we report the normative data (gathered in a large Italian population) of a short test that assess the ability to detect stimuli characterized by a conjunction of features: the 'Multiple Features Targets Cancellation' task (MFTC). Our sample of 465 subjects was composed by urban and rural people. Multiple linear regression analyses revealed significant relation of false alarms with age and educational level, and of time of execution with age, educational level and gender. Regression analyses on accuracy scores did not show any significant correlation with demographics variables. Based on non-parametric techniques, cutoff scores were obtained on the corrected scores of the patients, and equivalent scores were derived for each measure. The MFTC task represents a useful tool that explores attentional disorders (and in particular conjunction search disturbances) and that could be helpful both in discriminating different forms of dementia and to detect mild cognitive impairment patients at risk of conversion to dementia.