Effect of Nordic Sensi® Chair on Behavioral and Psychological Symptoms of Dementia in Nursing Homes Residents: A Randomized Controlled Trial.

BACKGROUND: Behavioral and psychological symptoms of dementia (BPSD) are present in most people with dementia (PwD), including Alzheimer's disease. There is consensus that non-pharmacological therapies represent the first line of treatment to address BPSD. OBJECTIVE: We explore the efficacy of the use of a rocking chair (Nordic Sensi® Chair, NSC) in the treatment of BPSD in nursing home residents with moderate and severe dementia. METHODS: We carried out a 16-week randomized, single-blind, controlled, clinical trial with PwD admitted to nursing homes. Participants were assigned to a treatment group (n = 40) that received three times a week one session per day of 20 minutes in the NSC and a control group (n = 37). The Neuropsychiatric Inventory-Nursing Home (NPI-NH) was used as primary efficacy outcome. Occupational distress for the staff was evaluated using the NPI-NH Occupational Disruptiveness subscale (NPI-NH-OD). Statistical analyses were conducted by means of a Mixed Effects Model Analysis. RESULTS: Treatment with the NSC was associated with a beneficial effect in most of BPSD, as reflected by differences between the treatment and control group on the NPI-NH total score (mean change score -18.87±5.56 versus -1.74±0.67, p = 0.004), agitation (mean change score -2.32±2.02 versus -0.78±1.44, p = 0.003) and irritability (mean change score -3.35±2.93 versus -1.42±1.31, p = 0.004). The NPI-NH-OD total score also improved the most in the treatment group (mean change score -9.67±7.67 versus -7.66±6.08, p = 0.003). CONCLUSIONS: The reduction in overall BPSD along with decreased caregiver occupational disruptiveness represent encouraging findings, adding to the potential of nonpharmacological interventions for nursing home residents living with dementia.

Multimodal integration of time.

Recent studies suggest that the accuracy of duration discrimination for visually presented intervals is strongly impaired by concurrently presented auditory intervals of different duration, but not vice versa. Because these studies rely mostly on accuracy measures, it remains unclear whether this impairment results from changes in perceived duration or rather from a decrease in perceptual sensitivity. We therefore assessed complete psychometric functions in a duration discrimination task to disentangle effects on perceived duration and sensitivity. Specifically, participants compared two empty intervals marked by either visual or auditory pulses. These pulses were either presented unimodally, or accompanied by task-irrelevant pulses in the respective other modality, which defined conflicting intervals of identical, shorter, or longer duration. Participants were instructed to base their temporal judgments solely on the task-relevant modality. Despite this instruction, perceived duration was clearly biased toward the duration of the intervals marked in the task-irrelevant modality. This was not only found for the discrimination of visual intervals, but also, to a lesser extent, for the discrimination of auditory intervals. Discrimination sensitivity, however, was similar between all multimodal conditions, and only improved compared to the presentation of unimodal visual intervals. In a second experiment, evidence for multisensory integration was even found when the task-irrelevant modality did not contain any duration information, thus excluding noncompliant attention allocation as a basis of our results. Our results thus suggest that audiovisual integration of temporally discrepant signals does not impair discrimination sensitivity but rather alters perceived duration, presumably by means of a temporal ventriloquism effect.

Temporal Preparation Driven by Rhythms is Resistant to Working Memory Interference.

It has been recently shown that temporal orienting demands controlled attention (Capizzi et al., 2012). However, there is current debate on whether temporal preparation guided by regular rhythms also requires the generation of endogenous temporal expectancies or rather involves a mechanism independent of executive control processes. We investigated this issue by using a dual-task paradigm in two different experiments. In Experiment 1, the single-task condition measured reaction time to respond to the onset of an auditory stimulus preceded by either a regular or an irregular auditory rhythm. The dual-task condition additionally included a working memory task, which demanded mental counting and updating. In Experiment 2, the simultaneously WM task was a variant of the Sternberg Task. We hypothesized that, if temporal preparation induced by rhythms did not involve executive processing, it would not be interfered by the simultaneous working memory task. The results showed that participants could anticipate the moment of target onset on the basis of the regular rhythm and, more important, this ability resisted the interference from the double task condition in both experiments. This finding supports that temporal preparation induced by rhythms, in contrast to temporal orienting, does not require resources of executive control.