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Introduction Mild cognitive impairment (MCI) prodromic of vascular dementia is expected to have a multidomain profile. Methods In a sample of cerebral small vessel disease (SVD) patients, we assessed MCI subtypes distributions according to different operationalization of Winblad criteria and compared the neuroimaging features of single versus multidomain MCI. We applied three MCI diagnostic scenarios in which the cutoffs for objective impairment and the number of considered neuropsychological tests varied. Results Passing from a liberal to more conservative diagnostic scenarios, of 153 patients, 5% were no longer classified as MCI, amnestic multidomain frequency decreased, and nonamnestic single domain increased. Considering neuroimaging features, severe medial temporal lobe atrophy was more frequent in multidomain compared with single domain. Discussion Operationalizing MCI criteria changes the relative frequency of MCI subtypes. Nonamnestic single domain MCI may be a previously nonrecognized type of MCI associated with SVD.

After several years of theoretical studies and laboratory experiments, the ATM tech- nique has now reached a sufficient degree of maturity that makes it ready to be experimented in the field. ATM substantially differs from traditional switching and transmission techniques for the statistical multiplexing introduced by the asynchronous technique. It turns out that the testing pro- cess is a formidable challenge for the operator, due to both the functional complexity foreseen for the B-ISDN switching systems and to the sophisticated performance issues involved. This paper is devoted to a first assessment of the relatively unexplored problem of specifying ATM switching equipment and testing its conformance to the specification. It begins by reviewing some concepts regarding the testing of existing switching systems, then examines the peculiarities of ATM, out- lines the main critical issues and their possible solution.

Purpose: the aim of this experimental study was to evaluate the attention modulating actions on the polysynaptic component of blink reflex responses and especially of the R3 component in patients suffering from Parkinson's Disease (PD). To this end, a non-task warning paradigm was adopted. Methods: attention processing was evaluated by means of a non-task paradigm in 55 patients suffering from PD. Subjects were presented with a visual ‘warning’ prestimulus and the blink reflex (BR) analyzed with special regard for any modulation of its polysynaptic components (R2–R3). Results: The mean amplitude of the post-warning R3 component (PW-R3c) of ‘de novo’ PD patients was 62% of the corresponding component following unannounced stimuli, a figure which differs significantly from both treated PD patients (18.9%) and control subjects (15.4%). De novo patients subsequently started on l-dopa therapy exhibited a more pronounced inhibition of the R3 component after warning stimulus, as the PW-R3c percentage decreased. Inversely, treated patients whose therapy was withheld showed decreased inhibition of this component. Regarding R2, the mean PW-R2c in the de novo patients differed slightly from that of the treated patients (P

The effects of a prestimulus on the electrically elicited blink reflex components were investigated in 20 healthy subjects. In the first group of 10 subjects (warned group), electric shocks were delivered in isolation or preceded, at an interstimulus interval (ISI) of 0.1 s, 1 s, or 10 s, by a visual or acoustic warning stimulus. In the second group of 10 subjects (unwarned group), the electric shocks were delivered either in isolation or preceded, at the same ISI, by visual or acoustic stimuli having no warning value. The modulation of the three blink reflex components was then analysed. Compared to the baseline condition, the R1 oligosynaptic component was enhanced at 0.1 s and 1 s ISI, in the warned group with the visual prestimulus, but only at 0.1 s after a visual and acoustic prestimulus in the unwarned group. On the contrary, the polysynaptic responses showed a different course: R2 was significantly reduced at the 0.1 s interval in the warned group with both the prestimuli, and only with the visual prestimulus in the unwarned group. The R3 was inhibited at all three intervals with the visual prestimulus, and at the 0.1 s and 1 s with the acoustic one in the warned group, and only at 0.1 s in the unwarned group, both after visual and acoustic prestimuli. The decrement in R2 and R3 observed with the shortest interval was probably related to the prepulse inhibition of startle reflex. Furthermore, only R3 was still inhibited at longer intervals, when the sustained processes of attention may have influenced this component. Perhaps this combination of events represents, in the warned group, the best preparation for voluntary reflex reaction.