Habituation of Brain Activity with Repetition in Color and Picture-Word Stroop Tests.

As a widely used mental task for functional near-infrared spectroscopy (fNIRS), the original color-word Stroop task has the advantage of being difficult to habituate, but also the disadvantage of being difficult to understand, especially for children. While the introduction of derived Stroop tasks offers highly promising countermeasures, changes in brain activity during these tests have not been well tested. We investigated the degree of habituation between the original and a derived Stroop task by measuring brain activity to obtain a better fNIRS task design. Fourteen healthy adults participated in the study, and a 10-channel fNIRS device was used. A picture-word Stroop task with lower linguistic conflict than the original was conducted. The original and derived Stroop tests were repeated four times in a 1-week interval. We found that the original Stroop test did not show any significant changes in brain activity with repeated measures; however, brain activity decreased during the derived test. The differences in habituation between the original and derived tests may be due to the differences in the strength of the linguistic conflict. Our findings also highlight the need to consider the effects of habituation when using derived Stroop tasks in repeated measures.

Hemodynamic changes in the right ventrolateral prefrontal cortex relate to the psychological mood profile.

Previous reports indicate that the right ventrolateral prefrontal cortex (VLPFC) is involved in emotional regulation. However, most such studies were performed under unphysiological conditions, like the administration of transcranial direct current or repetitive transcranial magnetic stimulation. We have shown that the right VLPFC is stimulated by an acute bout of daily activity, such as cleaning. Here, we investigated the relationship between the right VLPFC and mood changes using this system. Fourteen young adults vacuumed a floor as a cleaning task and kept a standing position as a control task on separate days. The oxyhemoglobin (oxy-Hb) and deoxy-hemoglobin (deoxy-Hb) signals of the prefrontal cortex were measured during the tasks. The mood scale scores of Profile of Mood States 2nd edition (POMS) and Two-Dimensional Mood Scale (TDMS) were measured before and after both tasks. The differences in subscale scores between pre- and post-tasks in both scales were calculated as ΔPOMS and ΔTDMS. The cleaning task significantly increased the oxy-Hb signal in the bilateral VLPFC and right frontopolar, but did not affect the deoxy-Hb signals. The control task significantly decreased the oxy-Hb signal in some brain regions. The Confusion-Bewilderment score in POMS changed after the cleaning task. Importantly, the oxy-Hb signal in the right VLPFC was negatively correlated with the ΔPOMS Confusion-Bewilderment score. The activity of the right VLPFC stimulated by the cleaning task might have a correlation with the Confusion-Bewilderment mood state.

Effect of one-session focused attention meditation on the working memory capacity of meditation novices: A functional near-infrared spectroscopy study.

INTRODUCTION: Previous studies have revealed that one-session focused attention meditation (FAM) can improve top-down attention control, which is one of the factors of working memory capacity (WMC). In addition, FAM shares various neural substrates, including the dorsolateral prefrontal cortex (DLPFC), with WMC. Thus, we hypothesized that one-session FAM would improve WMC by activating the DLPFC evoked by the top-down attention control. In this study, we examined whether FAM modified WMC in individuals with little to no meditation experience. METHODS: The participants were randomly assigned to either the FAM group (N = 13) or the control group (N = 17) who engaged in random thinking (i.e., mind-wandering). Before and after each 15-min intervention, the participants' WMC was measured according to the total number of correct answers in the Reading Span Test. During each intervention, functional near-infrared spectroscopy was employed to measure the blood flow in the participants' DLPFC and determine the top-down attention control effect. RESULTS: In the FAM group, WMC increased, and the bilateral DLPFC was activated during the intervention. As for the control group, WMC decreased after the intervention, and the bilateral DLPFC was not activated during the intervention. A correlation was also found among all participants between the increase in WMC and the activation of the bilateral DLPFC. CONCLUSION: The study findings suggest that top-down attention control during FAM can activate the bilateral DLPFC and increase WMC among meditation novices.

Factors affecting the performance of activities of daily living in patients with advanced cancer undergoing inpatient rehabilitation: results from a retrospective observational study.

[Purpose] Many clinicians believe that rehabilitation for patients with advanced cancer is futile. We determined factors affecting the performance of activities of daily living in patients with advanced cancer based on age, gender, marital status, living arrangement, rehabilitation intensity, type of cancer, impairment, metastasis, and active cancer treatment. [Participants and Methods] We assessed the Barthel Index to evaluate the performance of activities of daily living. Of the 120 adult patients with cancer who underwent inpatient rehabilitation, we analyzed the Barthel Index scores, consisting of 10 items, and reviewed the clinical characteristics from the medical records of 48 patients who completed supportive or palliative rehabilitation according to Dietz and showed an increased or maintained total Barthel Index score at final evaluation. [Results] The median total Barthel Index score increased from 45 (5-95) to 72.5 (5-100); the rehabilitation intensity was 320 (40-1,240) minutes. The analytical results showed that the increase of total Barthel Index score was positively associated with rehabilitation intensity (ß=0.350) and negatively associated with the initial grooming score (ß=-0.277). [Conclusion] Adequate rehabilitation positively affects performance of activities of daily living, especially in patients with advanced cancer who lost their grooming ability at the onset of rehabilitation. Importantly, rehabilitation may be beneficial for patients with advanced cancer.

An acute bout of housework activities has beneficial effects on executive function.

PURPOSE: Although acute bouts of exercise reportedly have beneficial effects on executive function, inactive people may find it difficult to start exercising. In this study, we focused on housework activities (HAs) that generate a sense of accomplishment and require a mild intensity of physical activity. We examined the impact of an acute bout of HA on executive function and oxygenated hemoglobin (oxy-Hb) flow to related cortical regions. MATERIALS AND METHODS: Twenty-five participants (age, 18-21 years; mean, 19.88±0.60 years; six males and 19 females) underwent two experiments, ie, HA and control experiments, which were conducted on different days. Participants vacuumed a dirty floor in the HA experiment and mimicked the same motion with an unplugged vacuum cleaner on a clean floor in the control experiment. RESULTS: Heart rate recorded during the experiments showed no significant difference in the intensity of physical activity between control and HA groups. A questionnaire revealed a sense of accomplishment after completing the HA experiment. Participants performed the Stroop color-word task (SCWT) pre- and post-experiments; cortical hemodynamic changes were simultaneously monitored using functional near-infrared spectroscopy. Variation in Stroop interference scores for SCWT total response between pre- and post-experiments was signifi-cantly higher in the HA group than in the control group, and that for SCWT correct response showed a similar trend. Variation in the Stroop interference score for oxy-Hb flow to the right ventrolateral prefrontal cortex (R-VLPFC) showed the same trend. CONCLUSION: Thus, HAs may have a greater beneficial effect on executive function than other physical activities through the activation of PFC, including R-VLPFC.

Relationship among motor function, ADL disability, and psychological concerns in elderly people with locomotive disorders.

BACKGROUND: Locomotive disorders are one of the main causative pathologies for the condition requiring assistance on activities of daily living (ADL). Although psychological concerns such as feeling of depression and anxiety are prevalent in elderly people, the causal relation among motor function, ADL disability, and psychological concerns is controversial. PURPOSE: Purpose of this study was to investigate causal relationship among motor function, ADL disability, and psychological concerns in elderly people with locomotive disorders. METHODS: The data for this study were from a community-dwelling sample of 314 elderly persons with locomotive disorders aged 65 and older who visited orthopedic clinics and/or affiliated institutions. Motor function was assessed by one-leg standing time with eyes open, leg extension power and grip power. We assessed ADL disability using the 25-question Geriatric Locomotive Function Scale (GLFS-25), and psychological concerns by three self-reported questions. We constructed two models and tested fitness of the models to the data using a structural equation modeling (SEM). Model 1: motor function affects ADL disability and ADL disability affects psychological concerns, Model 2: motor function affects psychological concerns and psychological concerns affects ADL disability. RESULTS: The fit indices were chi-square = 23.152 (p = 0.081), RMSEA = 0.042, GFI = 0.981, AGFI = 0.955, CFI = 0.987 for Model 1, and chi-square = 84.583 (p < 0.001), RMSEA = 0.119, GFI = 0.935, AGFI = 0.854, CFI = 0.892 for Model 2. These fit indices indicated a good fit of the model 1 and inadequate fit of model 2 to the data. CONCLUSION: Decline of motor function contributed toward psychological concerns via ADL disability in elderly people with locomotive disorders.

Post-stroke depression inhibits improvement in activities of daily living in patients in a convalescent rehabilitation ward.

[Purpose] There have been no investigations into the improvement of activities of daily living among patients suffering from post-stroke depression on admission to convalescent rehabilitation wards in Japan. This study aimed to assess the improvement of activities in daily living in patients with or without post-stroke depression at the time of admission to a convalescent rehabilitation ward. [Subjects and Methods] This retrospective study included 108 stroke patients divided into two groups according to their Geriatric Depression Scale 15-item short form scores. Activities of daily living were assessed using the Functional Independence Measure. The degree of improvement on the Functional Independence Measure was defined as the difference between scores on admission and at discharge. [Results] The Functional Independence Measure gain score was significantly different from the Functional Independence Measure total score. There was a significant interaction between time period and post-stroke depression factors for the Functional Independence Measure total score. A multiple regression analysis revealed a significant association between Geriatric Depression Scale score and Functional Independence Measure total score. [Conclusion] The present study suggests that post-stroke depression has a negative impact on recovery of activities of daily living and on rehabilitation outcomes in a convalescent rehabilitation ward setting.

Loss of ADAR1 in human iPS cells promotes caspase3-mediated apoptotic cell death.

Adenosine deaminases acting on RNA (ADARs) convert adenosine residues to inosine specifically in double-stranded RNAs. In this study, we investigated the function of primary RNA editing enzyme ADAR1 in pluripotent stem cells and found that loss of ADAR1 in human iPS cells promotes caspase3-mediated cell death. However, ADAR1 knockdown (KD) did not alter cell morphology, alkaline phosphatase (AP) staining activities and the expression levels of pluripotent marker genes, indicating that ADAR1 is dispensable for maintenance of pluripotency. Furthermore, ADAR1-KD iPS cells did not change proliferation rate. These findings extended the role of ADAR1 and might open the road for understanding pluripotent state more deeply.

Activation of the prefrontal cortex while performing a task at preferred slow pace and metronome slow pace: a functional near-infrared spectroscopy study.

Individuals have a preferred pace at which they perform voluntary repetitive movements. Previous studies have reported that greater activation of the prefrontal cortex was observed during self-initiated movements than during externally triggered movements. The purpose of the present study is to compare the activation of the prefrontal cortex induced when the subjects performed a peg-board task at their preferred slow pace (PSP, the self-initiated condition) with that induced when they performed the same task at metronome slow pace (MSP, the externally triggered condition) using functional near-infrared spectroscopy. Healthy subjects performed the task while sitting in a chair. By assessing the activated channels individually, we confirmed that all of the prefrontal regions of interest were activated by both tasks. In the second-level analyses, we found that the activation detected in the frontopolar cortex (FPPFC; Brodmann area 10) was higher during the PSP task than during the MSP task. The FPPFC is known to be at the top of prefrontal hierarchy, and specifically involved in evaluating self-generated information. In addition, the FPPFC plays a role in coordinating lateral prefrontal cortex. In the present study, the subjects evaluated and managed the internally generated PSP by coordinating the activity of other lower level prefrontal regions.