Ana Buján

Effects of Multisensory Stimulation on a Sample of Institutionalized Elderly People With Dementia Diagnosis A Controlled Longitudinal Trial

Long-term effects of multisensory stimulation were assessed using a “Snoezelen” room on older residents with dementia. Thirty patients were randomly assigned to 3 groups: multisensory stimulation environment (MSSE) group, individualized activities (activity) group, and control group. The MSSE and activity groups participated in two 30-minute weekly individualized intervention sessions over 16 weeks. Pre-, mid-, posttrial, and 8-week follow-up behavior, mood, cognitive, and functional impairment in basic activities of daily living were registered. Items included in the physically nonaggressive behavior factor improved significantly in post- versus pretrial in the MSSE group compared to the activity group, with no significant differences between MSSE and control groups. The MSSE and activity groups demonstrated behavior improvements and higher scores on the Cohen-Mansfield agitation inventory, verbal agitated behavior factor, and Neuropsychiatric Inventory–Nursing Home, with no significant differences between groups. The MSSE could have long-term positive effects on such neuropsychiatric symptoms in older people with dementia.

Classification of single normal and Alzheimer's disease individuals from cortical sources of resting state EEG rhythms

Previous studies have shown abnormal power and functional connectivity of resting state electroencephalographic (EEG) rhythms in groups of Alzheimers disease (AD) compared to healthy elderly (Nold) subjects. Here we tested the best classification rate of 120 AD patients and 100 matched Nold subjects using EEG markers based on cortical sources of power and functional connectivity of these rhythms. EEG data were recorded during resting state eyes-closed condition. Exact low-resolution brain electromagnetic tomography (eLORETA) estimated the power and functional connectivity of cortical sources in frontal, central, parietal, occipital, temporal, and limbic regions. Delta (2–4 Hz), theta (4–8 Hz), alpha 1 (8–10.5 Hz), alpha 2 (10.5–13 Hz), beta 1 (13–20 Hz), beta 2 (20–30 Hz), and gamma (30–40 Hz) were the frequency bands of interest. The classification rates of interest were those with an area under the receiver operating characteristic curve (AUROC) higher than 0.7 as a threshold for a moderate classification rate (i.e., 70%). Results showed that the following EEG markers overcame this threshold: (i) central, parietal, occipital, temporal, and limbic delta/alpha 1 current density; (ii) central, parietal, occipital temporal, and limbic delta/alpha 2 current density; (iii) frontal theta/alpha 1 current density; (iv) occipital delta/alpha 1 inter-hemispherical connectivity; (v) occipital-temporal theta/alpha 1 right and left intra-hemispherical connectivity; and (vi) parietal-limbic alpha 1 right intra-hemispherical connectivity. Occipital delta/alpha 1 current density showed the best classification rate (sensitivity of 73.3%, specificity of 78%, accuracy of 75.5%, and AUROC of 82%). These results suggest that EEG source markers can classify Nold and AD individuals with a moderate classification rate higher than 80%.

Predictors of caregiving satisfaction in informal caregivers of people with dementia

OBJECTIVE The prevalence of dementia is increasing and consequently the demands from families, institutions and healthcare system. Although a substantial amount of research on caregiving has emphasized the negative aspects of caregiving, specifically on caregiver burden and depression, less attention has been paid to the positive aspects of caregiving. The aim of the present work was to study the phenomenon of caregiving satisfaction in informal caregivers of people with dementia by assessing their likely predictors. METHODS A stress process model was used to study caregivers satisfaction (measured using the Revised Caregiving Satisfaction Scale) on 101 informal caregivers of patients with dementia in relation to the caregivers background and context, stress-related factors, and mediators. RESULTS The regression model has an adjusted R(2) of 0.20, which indicates that having a consanguinity relationship with the care recipient, suffering from lower levels of subjective burden, and managing individuals with severe cognitive impairment are the most important predictors of higher caregiving satisfaction. CONCLUSION Interventions focused on the enhancement of the caregiving satisfaction by increasing the understanding of the disease, should be especially addressed to caregivers without a consanguinity relationship and with high levels of subjective burden, and to those managing care recipients with mild or moderate stages of dementia.

Movement related cortical potentials in a face naming task: Influence of the tip-of-the-tongue state

The aim of the present study was evaluate the movement-related cortical potentials (MRCPs) associated with manual and speech movements during a face naming task carried out by the same participants as in a previous study, in order to: 1) determine whether the slowing down of the reaction time observed in the tip-of-the-tongue (TOT) state was caused by motor processes; 2) compare the MRCPs among the three response categories (tip-of-the-tongue, successful retrieval and not knowing the name); and 3) determine whether the MRCPs modulated the differences in amplitude of the late negative wave among response categories. The first component of readiness potential, the negative slope, the motor potential and the reafferent potential associated with the manual response, and two components associated with the verbal responses-the speech-related motor potential and the speech-related reafferent potential-were identified. The slowing down of reaction time observed in the TOT category may be due to a temporal interruption in the motor programming of the responses due to the TOT state. The longer latency in speech-related components in the KNOW with respect to the TOT category can be attributed to the greater cognitive demands involved in the retrieval of proper names in the former category. The brain activity associated with the preparation and execution of the responses had a differential modulatory effect on the amplitude of the LNW component, which may partially explain the differences between the categories observed in the previous study by Díaz et al. [Díaz, F., Lindín, M., Galdo-Alvarez, S., Facal, D., Juncos-Rabadán, O., 2007. An event-related potentials study of face identification and naming: the tip-of-the-tongue state. Psychophysiology 44, 50-68].

Efficacy of a computerized cognitive training application on cognition and depressive symptomatology in a group of healthy older adults: A randomized controlled trial

OBJECTIVE The purpose of this study was to evaluate the efficacy of a multimedia and interactive cognitive program on cognition and depressive symptomatology in healthy older adults. METHODS Adults aged ≥65 years were randomly assigned to two groups: the experimental group in which the participants received a computerized cognitive training application; and the control group in which the participants received no intervention during the protocol. Performance on the mini-mental state examination (MMSE) and the short-form of the geriatric depression scale (GDS-SF) were analysed using a three-way repeated-measure analysis of variance. RESULTS To determine cognition after the training, the cognitive program was used and the results were assessed using the MMSE, indicating that the significant time effects within the groups reflected the score for cognitive assessment that was significantly better after the intervention in the experimental group. No significant differences were observed with regard to the depressive symptomatology or between the groups according to sex or educational level on the two dimensions previously established (cognition and depressive symptomatology). CONCLUSION The development of technological applications for intervention in older adults is increasing. Based on the established objective, we can conclude that the computerized intervention may constitute a good alternative to enhance the cognitive status in older people.

An event-related potentials study of face naming: Evidence of phonological retrieval deficit in the tip-of-the-tongue state

A famous-face naming task was used to establish the electrophysiological characterization of the tip-of-the-tongue (TOT) state, successful naming (K), and nonrecognition (DK). The differences in the direct event-related potentials (ERPs) and in the lateralized readiness potential between those categories were studied. The ERP correlates of recognition and access to semantic and lexical information were similar between K and TOT, but showed amplitude differences with respect to DK. A delayed onset of the response selection was obtained in TOT in comparison with K, suggesting an insufficient activation of phonological information from 360 ms onwards. The continuous search for the name and the conflict monitoring in TOT led to differences in ERP amplitudes between TOT and the other categories from 750 ms onwards as well as to a delayed onset of response preparation, indicating a continuous engagement of processing resources.

Cortical Neural Synchronization Underlies Primary Visual Consciousness of Qualia: Evidence from Event-Related Potentials

This article reviews three experiments on event-related potentials (ERPs) testing the hypothesis that primary visual consciousness (stimulus self-report) is related to enhanced cortical neural synchronization as a function of stimulus features. ERP peak latency and sources were compared between “seen” trials and “not seen” trials, respectively related and unrelated to the primary visual consciousness. Three salient features of visual stimuli were considered (visuospatial, emotional face expression, and written words). Results showed the typical visual ERP components in both “seen” and “not seen” trials. There was no statistical difference in the ERP peak latencies between the “seen” and “not seen” trials, suggesting a similar timing of the cortical neural synchronization regardless the primary visual consciousness. In contrast, ERP sources showed differences between “seen” and “not seen” trials. For the visuospatial stimuli, the primary consciousness was related to higher activity in dorsal occipital and parietal sources at about 400 ms post-stimulus. For the emotional face expressions, there was greater activity in parietal and frontal sources at about 180 ms post-stimulus. For the written letters, there was higher activity in occipital, parietal and temporal sources at about 230 ms post-stimulus. These results hint that primary visual consciousness is associated with an enhanced cortical neural synchronization having entirely different spatiotemporal characteristics as a function of the features of the visual stimuli and possibly, the relative qualia (i.e., visuospatial, face expression, and words). In this framework, the dorsal visual stream may be synchronized in association with the primary consciousness of visuospatial and emotional face contents. Analogously, both dorsal and ventral visual streams may be synchronized in association with the primary consciousness of linguistic contents. In this line of reasoning, the ensemble of the cortical neural networks underpinning the single visual features would constitute a sort of multi-dimensional palette of colors, shapes, regions of the visual field, movements, emotional face expressions, and words. The synchronization of one or more of these cortical neural networks, each with its peculiar timing, would produce the primary consciousness of one or more of the visual features of the scene.

Multisensory Stimulation and Individualized Music Sessions on Older Adults with Severe Dementia: Effects on Mood, Behavior, and Biomedical Parameters

BACKGROUND Multisensory stimulation and individualized music have shown to be good in handling the psychological and behavioral symptoms in people with severe dementia. OBJECTIVE Explore the effects of two nonpharmacological interventions, multisensory stimulation environment (MSSE) in a Snoezelen room and individualized music sessions, on mood, behavior, and biomedical parameters of institutionalized elderly patients with severe dementia. METHODS Randomized trial of 21 patients aged ≥65 years randomly assigned to two groups (MSSE and individualized music). Interventions administered in two-weekly sessions lasted 30 minutes for a period of 12 weeks. Main outcomes were recorded before, during, and at the end of the intervention. RESULTS Both groups had immediate positive effects on mood and behavior. Participants were more happy/more content (p < 0.001), talked more spontaneously (p = 0.009), related to people better (p = 0.002), were more attentive to/focused on their environment (p < 0.001), enjoyed themselves (p = 0.003), were less bored/inactive (p = 0.004), and more relaxed/content (p = 0.003). The MSSE group performed a better visual follow-up of the stimuli (p = 0.044), and the music group were more relaxed and happy (p = 0.003). A decrease in heart rate (p = 0.013) and an increase in oxygen saturation (p = 0.011) were observed from before to after interventions in both groups, with no significant differences between them. CONCLUSIONS Both interventions seem to be effective at managing mood and behavioral disturbances in the short term and at improving physiological rates, highlighting the efficacy of nonpharmacological treatments in patients with severe dementia.

Preserved Suppression of Salient Irrelevant Stimuli During Visual Search in Age-Associated Memory Impairment

Previous studies have suggested that older adults with age-associated memory impairment (AAMI) may show a significant decline in attentional resource capacity and inhibitory processes in addition to memory impairment. In the present paper, the potential attentional capture by task-irrelevant stimuli was examined in older adults with AAMI compared to healthy older adults using scalp-recorded event-related brain potentials (ERPs). ERPs were recorded during the execution of a visual search task, in which the participants had to detect the presence of a target stimulus that differed from distractors by orientation. To explore the automatic attentional capture phenomenon, an irrelevant distractor stimulus defined by a different feature (color) was also presented without previous knowledge of the participants. A consistent N2pc, an electrophysiological indicator of attentional deployment, was present for target stimuli but not for task-irrelevant color stimuli, suggesting that these irrelevant distractors did not attract attention in AAMI older adults. Furthermore, the N2pc for targets was significantly delayed in AAMI patients compared to healthy older controls. Together, these findings suggest a specific impairment of the attentional selection process of relevant target stimuli in these individuals and indicate that the mechanism of top-down suppression of entirely task-irrelevant stimuli is preserved, at least when the target and the irrelevant stimuli are perceptually very different.