Stopwatch training improves cognitive functions in patients with Parkinson's disease.

Parkinson's disease (PD) impairs various cognitive functions, including time perception. Dysfunctional time perception in PD is poorly understood, and no study has investigated the rehabilitation of time perception in patients with PD. We aimed to induce the recovery of time perception in PD patients and investigated the potential relationship between recovery and cognitive functions/domains other than time perception. Sixty patients with PD (27 females) and 20 healthy controls (10 females) were recruited. The participants underwent a feedback training protocol for 4 weeks to improve the accuracy of subjective spatial distance or time duration using a ruler or stopwatch, respectively. They participated in three tests at weekly intervals, each comprising 10 types of cognitive tasks and assessments. After duration feedback training for 1 month, performance on the Go/No-go task, Stroop task, and impulsivity assessment improved in patients with PD, while no effect was observed after distance feedback training. Additionally, the effect of training on duration production correlated with extended reaction time and improved accuracy in the Go/No-go and Stroop tasks. These findings suggest that time perception is functionally linked to inhibitory systems. If the feedback training protocol can modulate and maintain time perception, it may improve various cognitive/psychiatric functions in patients with PD. It may also be useful in the treatment of diseases other than PD that cause dysfunctions in temporal processing.

Analgesia Is Enhanced by Providing Information regarding Good Outcomes Associated with an Odor: Placebo Effects in Aromatherapy?

No previous report has described whether information regarding an odor used in aromatherapy has placebo effects. We investigated whether placebo analgesia was engendered by verbal information regarding the analgesic effects of an odor. Twelve of 24 subjects were provided with the information that a lavender odor would reduce pain (informed), whereas the other 12 subjects were not (not-informed). Concurrent with respiration recording, the subjects were administered a lavender-odor or no-odor treatment during application of painful stimulation to the forefinger. The subjects reported their experience of pain and its unpleasantness on a visual analogue scale after the painful stimulation. The lavender-odor treatment significantly alleviated pain and unpleasantness compared with the no-odor treatment in the informed (P < 0.01) and not-informed groups (P < 0.05). The no-odor treatment in the informed group significantly alleviated pain and unpleasantness compared with both the no-odor and lavender-odor treatments in the not-informed group (P < 0.05). Rapid and shallow breathing induced by the painful stimulation became slow and deep during the lavender-odor and no-odor treatments in both groups. Information regarding a lavender odor, the lavender odor itself, and slower breathing contributed to reduced perceptions of pain and unpleasantness during painful stimulation, suggesting that placebo effects significantly contribute to analgesia in aromatherapy.

Sound localization difficulty affects early and late processing of auditory spatial information: investigation using the dipole tracing method.

OBJECTIVE: To understand the functional roles of brain regions related in the auditory spatial localization, we recorded auditory event-related potentials (ERPs) and estimated their source generators using the dipole tracing method. METHODS: Target sound stimuli perceived as coming from two directions (-90 degrees, +90 degrees where 0 degrees was straight behind the subject within the azimuth in the interaural plane) were randomly presented with two distracter stimuli for providing difficulty of detection. The distracter stimuli were 75 degrees behind the target stimuli (easy task) and 45 degrees behind the target stimuli (difficult task). RESULTS: Compared with the passive listening tasks, distinct potentials appeared in the easy task at the early (110-150 ms: N1-late) time windows of ERPs and in the difficult task at the late (450-800 ms: slow wave, SW) time windows of ERPs. Dipoles were estimated to be at the posterior auditory cortex, precuneus and thalamus for N1-late, and the middle/inferior frontal gyrus, anterior region of superior temporal gyrus and parahippocampal gyrus for SW for both tasks. CONCLUSIONS: Difficulty of sound localization may affect brain function related to analyzing features of the spatial cue, eventually identifying the spatial location, and attention. SIGNIFICANCE: Brain regions responsible for sound localization may show different activity patterns depending on the functional roles of each brain region.