Enhanced audiovisual integration with aging in speech perception: a heightened McGurk effect in older adults

Two experiments compared young and older adults in order to examine whether aging leads to a larger dependence on visual articulatory movements in auditory-visual speech perception. These experiments examined accuracy and response time in syllable identification for auditory-visual (AV) congruent and incongruent stimuli. There were also auditory-only (AO) and visual-only (VO) presentation modes. Data were analyzed only for participants with normal hearing. It was found that the older adults were more strongly influenced by visual speech than the younger ones for acoustically identical signal-to-noise ratios (SNRs) of auditory speech (Experiment 1). This was also confirmed when the SNRs of auditory speech were calibrated for the equivalent AO accuracy between the two age groups (Experiment 2). There were no aging-related differences in VO lipreading accuracy. Combined with response time data, this enhanced visual influence for the older adults was likely to be associated with an aging-related delay in auditory processing

Right Prefrontal Activity Reflects the Ability to Overcome Sleepiness during Working Memory Tasks: A Functional Near-Infrared Spectroscopy Study

It has been speculated that humans have an inherent ability to overcome sleepiness that counteracts homeostatic sleep pressure. However, it remains unclear which cortical substrate activities are involved in the ability to overcome sleepiness during the execution of cognitive tasks. Here we sought to confirm that this ability to overcome sleepiness in task execution improves performance on cognitive tasks, showing activation of neural substrates in the frontal cortex, by using a modified n-back (2- and 0-back) working memory task and functional near-infrared spectroscopy. The change in alertness was just correlated with performances on the 2-back task. Activity in the right prefrontal cortex changed depending on alertness changes on the 2- and 0-back tasks independently, which indicates that activity in this region clearly reflects the ability to overcome sleepiness; it may contribute to the function of providing sufficient activity to meet the task load demands. This study reveals characteristics of the ability to overcome sleepiness during the n-back working memory task which goes beyond the attention-control function traditionally proposed

Regression of Necrotic Lesions after Methotrexate Withdrawal in Patients with Methotrexate-Associated Lymphoproliferative Disorders: A Retrospective CT Study

This retrospective study investigated whether necrotic lesions detected on a computed tomography (CT) scan are more regressive than non-necrotic lesions after methotrexate withdrawal in patients pathologically diagnosed with methotrexate-associated lymphoproliferative disorders (MTX-LPD). In total, 89 lesions extracted from 24 patients on CT scans were included in the analysis. All patients had been evaluated for the presence of necrosis within lesions via CT scan upon first suspicion of MTX-LPD (baseline CT scan). The percentage lesion size reduction between the baseline and initial follow-up CT scan was calculated. The association between necrosis within lesions and size changes was estimated via linear regression analyses using both crude and adjusted models. Necrosis was significantly more common in extranodal lesions (27 out of 30 lesions, 90%) than in nodal lesions (9 out of 59 lesions, 15%, p<0.001). In the crude model, the regression of necrotic lesions was 58.5% greater than that of non-necrotic lesions; the difference was statistically significant (p<0.001). Additionally, the longest diameter of necrotic lesions at the baseline CT scan was significantly greater than that of non-necrotic lesions (p<0.001). Based on the adjusted model, necrotic lesions showed 49.3% greater regression than non-necrotic lesions (p=0.017). Necrosis detected on a CT scan was found to be an independent predictor of regression after MTX withdrawal in patients with MTX-LPD

Musical instrument training program improves verbal memory and neural efficiency in novice older adults

楽器訓練で高齢者の認知機能が向上することを確認 --訓練による脳活動の変化を高齢者で初報告--. 京都大学プレスリリース. 2020-12-24.Previous studies indicate that musical instrument training may improve the cognitive function of older adults. However, little is known about the neural origins of training‐related improvement in cognitive function. Here, we assessed the effects of instrumental training program on cognitive functions and neural efficiency in musically naïve older adults (61–85 years old). Participants were assigned to either the intervention group, which received a 4‐month instrumental training program using keyboard harmonica, or a control group without any alternative training. Cognitive measurements and functional magnetic resonance imaging during visual working memory (VWM) task were administered before and after the intervention in both groups. Behavioral data revealed that the intervention group significantly improved memory performance on the test that measures verbal recall compared to the control group. Neuroimaging data revealed that brain activation in the right supplementary motor area, left precuneus, and bilateral posterior cingulate gyrus (PCgG) during the VWM task decreased after instrumental training only in the intervention group. Task‐related functional connectivity (FC) analysis revealed that the intervention group showed decreased FC between the right PCgG and left middle temporal gyrus, and between the left putamen and right superior temporal gyrus (lPu‐rSTG) during a VWM task after the intervention. Furthermore, a greater improvement in memory performance in the intervention group was associated with a larger reduction in lPu‐rSTG FC, which might be interpreted as improved neural efficiency. Our results indicate that the musical instrument training program may contribute to improvements in verbal memory and neural efficiency in novice older adults

Sleep Deprivation Influences Diurnal Variation of Human Time Perception with Prefrontal Activity Change: A Functional Near-Infrared Spectroscopy Study

Human short-time perception shows diurnal variation. In general, short-time perception fluctuates in parallel with circadian clock parameters, while diurnal variation seems to be modulated by sleep deprivation per se. Functional imaging studies have reported that short-time perception recruits a neural network that includes subcortical structures, as well as cortical areas involving the prefrontal cortex (PFC). It has also been reported that the PFC is vulnerable to sleep deprivation, which has an influence on various cognitive functions. The present study is aimed at elucidating the influence of PFC vulnerability to sleep deprivation on short-time perception, using the optical imaging technique of functional near-infrared spectroscopy. Eighteen participants performed 10-s time production tasks before (at 21:00) and after (at 09:00) experimental nights both in sleep-controlled and sleep-deprived conditions in a 4-day laboratory-based crossover study. Compared to the sleep-controlled condition, one-night sleep deprivation induced a significant reduction in the produced time simultaneous with an increased hemodynamic response in the left PFC at 09:00. These results suggest that activation of the left PFC, which possibly reflects functional compensation under a sleep-deprived condition, is associated with alteration of short-time perception

Effects of a 10-week musical instrument training on cognitive function in healthy older adults: implications for desirable tests and period of training

IntroductionPrevious studies have shown that musical instrument training programs of 16 or more weeks improve verbal memory (Logical Memory Test delayed recall), processing speed (Digit Symbol Coding Test), and executive function (Trail Making Test Part B) of musically untrained healthy older adults. However, it is unclear whether shorter-period instrument training can yield similar effects. We sought to (1) verify those results and (2) clarify if intervention effects could be detected using other measures such as reaction time.MethodsHealthy older adults (mean age = 73.28 years) were pseudo-randomly assigned to an untrained control group (n = 30) or an intervention group (n = 30) that received a weekly 10-session musical instrument training program (using melodica). We conducted neuropsychological tests on which intervention effects or association with musical training were reported in previous studies. We newly included two reaction time tasks to assess verbal working memory (Sternberg task) and rhythm entrainment (timing task). Intervention effects were determined using a “group × time” analysis of variance (ANOVA).ResultsThe intervention effects were detected on the reaction time in Sternberg task and phonological verbal fluency. Although intervention effects had been reported on Logical Memory test, Digit Symbol Coding Test and Trail Making Test in previous studies with longer training periods, the present study did not show such effects. Instead, the test-retest practice effect, indicated by significant improvement in the control group, was significant on these tests.DiscussionThe present results indicated the usefulness of working memory assessments (Verbal Fluency Test and Sternberg task) in detecting the effects of short-term melodica training in healthy older adults. The practice effect detected on those three tasks may be due to the shorter interval between pre- and post-intervention assessments and may have obscured intervention effects. Additionally, the findings suggested the requirement for an extended interval between pre- and post-tests to capture rigorous intervention effects, although this should be justified by a manipulation of training period

Absorption problems for quantum walks in one dimension

This paper treats absorption problems for the one-dimensional quantum walk determined by a 2 times 2 unitary matrix U on a state space {0,1,...,N} where N is finite or infinite by using a new path integral approach based on an orthonormal basis P, Q, R and S of the vector space of complex 2 times 2 matrices. Our method studied here is a natural extension of the approach in the classical random walk.Comment: 15 pages, small corrections, journal reference adde

Serum IgG4 as a biomarker reflecting pathophysiology and post-operative recurrence in chronic rhinosinusitis

Background: Type 2 chronic rhinosinusitis (CRS), especially eosinophilic CRS (ECRS), is an intractable upper airway inflammatory disease. Establishment of serum biomarkers reflecting the pathophysiology of CRS is desirable in a clinical setting. As IgG4 production is regulated by type 2 cytokines, we sought to determine whether serum IgG4 levels can be used as a biomarker for CRS. Methods: Association between the serum IgG4 levels and clinicopathological factors was analyzed in 336 CRS patients. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of serum IgG4 levels that can be used to predict the post-operative recurrence. Results: Serum IgG4 levels were significantly higher in patients with moderate to severe ECRS versus those with non to mild ECRS. The levels were also significantly higher in asthmatic patients and patients exhibiting recurrence after surgery compared to controls. ROC analysis determined that the best cut-off value for the serum IgG4 level to predict the post-operative recurrence was 95 mg/dL. The corresponding sensitivity and specificity were 39.7% and 80.5%, respectively. When we combined the two cut-off values for the serum IgG4 and periostin, patients with high serum levels of either IgG4 or periostin exhibited a high post-operative recurrence (OR: 3.95) as compared to patients having low serum levels of both IgG4 and periostin. Conclusions: The present results demonstrate that the serum IgG4 level is associated with disease severity and post-operative course in CRS. In particular, the combination of serum IgG4 and periostin could be a novel biomarker that predicts post-operative recurrence