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1.
PLoS One ; 19(4): e0301543, 2024.
Article En | MEDLINE | ID: mdl-38557587

This study aimed to explore the relationship between gray matter volume changes and various clinical parameters in patients with migraine, focusing on symptom severity, quality of life, and states of depression and anxiety. Using a case-control design, we examined 33 patients with migraine, with or without aura, and 27 age-matched healthy subjects. We used magnetic resonance imaging to assess the volumes of 140 bilateral brain regions. Clinical evaluations included the Migraine Disability Assessment, the Migraine Specific Quality of Life Questionnaire, the Center for Epidemiologic Studies Depression scale, Spielberger's State and Trait Anxiety scales, and the Japanese version of the Montreal Cognitive Assessment. We compared the scores of these measures between migraine patients and healthy controls to examine the interplay between brain structure and clinical symptoms. Significant volumetric differences were observed in the pallidum and amygdala between migraine patients and healthy individuals. The reduction in the right amygdala volume correlated significantly with migraine severity as measured by the Migraine Disability Assessment. Path analysis revealed a model where Migraine Disability Assessment scores were influenced by Migraine Specific Quality of Life Questionnaire outcomes, which were further affected by depression, anxiety, and a low right pallidum volume. Our findings suggest that the chronicity and severity of migraine headaches specifically affect the right amygdala. Our path model suggests a complex relationship whereby migraine disability is strongly influenced by quality of life, which is, in turn, affected by psychological states, such as anxiety and depression.


Migraine Disorders , Migraine with Aura , Humans , Quality of Life , Migraine Disorders/diagnosis , Brain , Anxiety , Magnetic Resonance Imaging
2.
Front Psychiatry ; 15: 1379496, 2024.
Article En | MEDLINE | ID: mdl-38686125

Time cognition is an essential function of human life, and the impairment affects a variety of behavioral patterns. Neuropsychological approaches have been widely demonstrated that Parkinson's disease (PD) impairs time cognitive processing. Many researchers believe that time cognitive deficits are due to the basal ganglia, including the striatum or subthalamic nucleus, which is the pathomechanism of PD, and are considered to produce only transient recovery due to medication effects. In this perspective, we focus on a compensatory property of brain function based on the improved time cognition independent of basal ganglia recovery and an overlapping structure on the neural network based on an improved inhibitory system by time cognitive training, in patients with PD. This perspective may lead to restoring multiple functions through single function training.

3.
Sci Rep ; 13(1): 7596, 2023 05 10.
Article En | MEDLINE | ID: mdl-37165097

Grief reactions to the bereavement of a close individual could involve empathy for pain, which is fundamental to social interaction. To explore whether grief symptoms interact with social relatedness to a person to whom one directs empathy to modulate the expression of empathy, we administered an empathy task to 28 bereaved adults during functional magnetic resonance imaging, in which participants were subliminally primed with facial stimuli (e.g., faces of their deceased or living relative, or a stranger), each immediately followed by a visual pain stimulus. Individuals' grief severity promoted empathy for the pain stimulus primed with the deceased's face, while it diminished the neural response to the pain stimulus primed with the face of either their living relative or a stranger in the medial frontal cortex (e.g., the right dorsal anterior cingulate cortex). Moreover, preliminary analyses showed that while the behavioral empathic response was promoted by the component of "longing" in the deceased priming condition, the neural empathic response was diminished by the component of "avoidance" in the stranger priming condition. Our results suggest an association between grief reactions to bereavement and empathy, in which grief symptoms interact with interpersonal factors to promote or diminish empathic responses to others' pain.


Empathy , Grief , Adult , Humans , Pain/pathology , Gyrus Cinguli/physiology , Frontal Lobe/pathology , Magnetic Resonance Imaging
4.
Front Psychol ; 14: 1161333, 2023.
Article En | MEDLINE | ID: mdl-37113119

Objective: Improving quality of life (QOL) after surgery is very important. Recently, preoperative anxiety has been suggested to predict postoperative health-related (HR) QOL, however the accuracy of anxiety measurement remains problematic. We examined the relationship between preoperative anxiety level and postoperative HRQOL using qualitative and quantitative assessment of anxiety. Method: We used a detailed anxiety assessment to quantitatively investigate preoperative anxiety as a predictor of postoperative HRQOL in lung cancer patients. Fifty one patients who underwent surgery for lung cancer were included. They were assessed four times: on admission, on discharge, 1 month after surgery, and 3 months after surgery. Anxiety was measured separately as "state anxiety" and "trait anxiety" using the State-Trait Anxiety Inventory, and HRQOL was measured using the EuroQol 5 dimension 5-level. Results: The HRQOL decreased at discharge and gradually recovered over time, reaching the same level at 3 months after surgery as at admission. HRQOL score was lower at discharge than at pre-surgery and 3 months after the surgery (p < 0.0001 each), and the score at 1 month after the surgery was lower than at pre-surgery (p = 0.007). In addition, multiple regression analysis showed that HRQOL at discharge was associated with "state anxiety" rather than "trait anxiety" at admission (p = 0.004). Conclusion: This study identifies the types of anxiety that affect postoperative HRQOL. We suggest that postoperative HRQOL on discharge may be improved by interventions such as psychological or medication treatment for preoperative state anxiety if identified preoperative state anxiety can be managed appropriately.

5.
Front Aging Neurosci ; 15: 1126618, 2023.
Article En | MEDLINE | ID: mdl-36875693

Background: Differences in the extent of cerebral white matter lesions (WML) and regional cerebral blood flow (rCBF) in early-stage cognitive impairment (ESCI) contribute to the prognosis of cognitive decline; however, it is unclear precisely how WML and rCBF affect cognitive decline in ESCI. Objective: We examined the association between WML, rCBF, and cognitive impairment in the ESCI, using path analysis to clarify how these variables affect each other. Methods: Eighty-three patients who consulted our memory clinic regarding memory loss were included in this study based on the Clinical Dementia Rating. Participants underwent the Mini-Mental State Examination (MMSE), brain magnetic resonance imaging (MRI) for voxel-based morphometry analysis, and brain perfusion single-photon emission computed tomography (SPECT) for rCBF evaluation in cortical regions, using 3D stereotactic surface projection (3D-SSP) analysis. Results: Path analysis was performed on the MRI voxel-based morphometry and SPECT 3D-SSP data, showing a significant correlation between both and MMSE scores. In the most suitable model (GFI = 0.957), correlations were observed between lateral ventricular (LV-V) and periventricular WML (PvWML-V) volumes [standardized coefficient (SC) = 0.326, p = 0.005], LV-V and rCBF of the anterior cingulate gyrus (ACG-rCBF; SC = 0.395, p < 0.0001), and ACG-rCBF and PvWML-V (SC = 0.231, p = 0.041). Furthermore, a direct relationship between PvWML-V and MMSE scores was identified (SC = -0.238, p = 0.026). Conclusion: Significant interrelationships were observed among the LV-V, PvWML-V, and ACG-rCBF that directly affected the MMSE score in the ESCI. The mechanisms behind these interactions and the impact of PvWML-V on cognitive function require further investigation.

6.
Front Aging Neurosci ; 15: 1090052, 2023.
Article En | MEDLINE | ID: mdl-36936495

Sense of time (temporal sense) is believed to be processed by various brain regions in a complex manner, among which the basal ganglia, including the striatum and subthalamic nucleus (STN), play central roles. However, the precise mechanism for processing sense of time has not been clarified. To examine the role of the STN in temporal processing of the sense of time by directly manipulating STN function by switching a deep brain stimulation (DBS) device On/Off in 28 patients with Parkinson's disease undergoing STN-DBS therapy. The test session was performed approximately 20 min after switching the DBS device from On to Off or from Off to On. Temporal sense processing was assessed in three different tasks (time reproduction, time production, and bisection). In the three temporal cognitive tasks, switching STN-DBS to Off caused shorter durations to be produced compared with the switching to the On condition in the time production task. In contrast, no effect of STN-DBS was observed in the time bisection or time reproduction tasks. These findings suggest that the STN is involved in the representation process of time duration and that the role of the STN in the sense of time may be limited to the exteriorization of memories formed by experience.

7.
Brain Behav ; 13(4): e2956, 2023 04.
Article En | MEDLINE | ID: mdl-36897168

INTRODUCTION: In patients with mild cognitive impairment, pathological changes begin in the amygdala (AMG) and hippocampus (HI), especially in the parahippocampal gyrus and entorhinal cortex (ENT). These areas play an important role in olfactory detection and recognition. It is important to understand how subtle signs of olfactory disability relate to the functions of the above-mentioned regions, as well as the orbitofrontal cortex (OFC). In this study, we evaluated brain activation using functional magnetic resonance imaging (fMRI), performed during the presentation of olfactory stimuli (classified as "normal odors" not inducing memory retrieval), and investigated the relationships of the blood oxygen level-dependent (BOLD) signal with olfactory detection and recognition abilities in healthy elderly subjects. METHODS: Twenty-four healthy elderly subjects underwent fMRI during olfaction, and raw mean BOLD signals were extracted from regions of interest, including bilateral regions (AMG, HI, parahippocampus, and ENT) and orbitofrontal subregions (frontal inferior OFC, frontal medial OFC, frontal middle OFC, and frontal superior OFC). Multiple regression and path analyses were conducted to understand the roles of these areas in olfactory detection and recognition. RESULTS: Activation of the left AMG had the greatest impact on olfactory detection and recognition, while the ENT, parahippocampus, and HI acted as a support system for AMG activation. Less activation of the right frontal medial OFC was associated with good olfactory recognition. These findings improve our understanding of the roles of limbic and prefrontal regions in olfactory awareness and identification in elderly individuals. CONCLUSION: Functional decline of the ENT and parahippocampus crucially impacts olfactory recognition. However, AMG function may compensate for deficits through connections with frontal regions.


Amygdala , Odorants , Humans , Aged , Amygdala/diagnostic imaging , Brain/physiology , Smell/physiology , Recognition, Psychology , Magnetic Resonance Imaging/methods
8.
Sci Rep ; 13(1): 920, 2023 01 17.
Article En | MEDLINE | ID: mdl-36650347

Change in body perception requires recalibration of various sensory inputs. However, it is less known how information other than sensations relates to the recalibration of body perception. Here, we focused on the relationship between respiration and cognition and investigated whether respiratory rhythms are related to the recalibration of hand perception. We built a visual feedback environment, in which a mannequin hand moved in conjunction with its own respiratory rhythm, and participants performed an experiment under conditions in congruency/incongruency for spatial and temporal factors. The temporal and spatial congruency between own respiratory rhythm and the mannequin hand markedly facilitated the phenomenon of hand ownership sense transfer to the mannequin hand, while incongruency had little effect on the change in hand ownership. The finding suggests that an internal model in the brain allows respiratory rhythms to be involved in the adaptation of the body's neural representations.


Illusions , Visual Perception , Humans , Brain , Cognition , Hand , Respiration
9.
Neuromodulation ; 25(4): 511-519, 2022 06.
Article En | MEDLINE | ID: mdl-35667769

OBJECTIVES: Time awareness may change depending on the mental state or disease conditions, although each individual perceives his/her own sense of time as stable and accurate. Nevertheless, the processes that consolidate altered duration production remain unclear. The present study aimed to manipulate the subjective duration production via memory consolidation through the modulation of neural plasticity. MATERIALS AND METHODS: We first performed false feedback training of duration or length production and examined the period required for natural recovery from the altered production. Next, persistent neural plasticity was promoted by quadripulse transcranial magnetic stimulation (QPS) over the right dorsolateral prefrontal cortex (DLPFC), temporoparietal junction (TPJ), and primary motor cortex (M1). We conducted the same feedback training in the individual and studied how the time course of false learning changed. RESULTS: We observed that altered duration production after false feedback returned to baseline within two hours. Next, immediate exposure to false feedback during neural plasticity enhancement revealed that in individuals who received QPS over the right DLPFC, but not over TPJ or M1, false duration production was maintained for four hours; furthermore, the efficacy persisted for at least one week. CONCLUSION: These findings suggest that, while learned altered duration production decays over several hours, QPS over the right DLPFC enables the consolidation of newly learned duration production.


Evoked Potentials, Motor , Motor Cortex , Evoked Potentials, Motor/physiology , Female , Humans , Male , Motor Cortex/physiology , Neuronal Plasticity/physiology , Prefrontal Cortex , Transcranial Magnetic Stimulation
10.
J Foot Ankle Res ; 15(1): 42, 2022 May 30.
Article En | MEDLINE | ID: mdl-35637529

BACKGROUND: It is unclear whether the toe grip force (TGF) of the dominant foot (DF) and the lower limb function asymmetry (LLFA) in older adults are associated with fall risk. Therefore, this study aimed to investigate the effect of lower limb properties (such as TGF, muscle strength, and plantar sensation) on the risk of falls in older adults, while considering the foot dominance and asymmetry of lower limb function. METHODS: This study was a cross-sectional study. We determined whether the lower limb function of the DF and non-dominant foot (non-DF) and LLFA had any effect on the fall risk in 54 older adults (mean ± standard deviation: 72.2 ± 6.0, range: 60-87 years). We examined the participants' fall history, Mini-Mental State Examination (MMSE) score, lower limb function, and LLFA. To determine fall risk factors, we performed logistic regression analysis, with presence or absence of falls as the dependent variable. RESULTS: The independent variables were age, sex, MMSE score, two-point discrimination of the heel (non-DF) as plantar sensation index, and the TGF of both feet. Only the TGF of the DF was identified as a risk factor for falls (p < 0.05). CONCLUSIONS: In older adults, clinicians should focus on the TGF of the DF as a risk factor for falls. TRIAL REGISTRATION: This study was retrospectively registered. https://center6.umin.ac.jp/cgi-bin/ctr/ctr_up_rec_f1.cgi .


Independent Living , Lower Extremity , Aged , Cross-Sectional Studies , Hand Strength , Humans , Toes/physiology
11.
Neurosci Res ; 182: 52-59, 2022 Sep.
Article En | MEDLINE | ID: mdl-35636589

New neurons are constantly generated in the olfactory bulb and the dentate gyrus of the hippocampus. The number of new cells depends on sensory experiences; an enriched odor environment increases neurogenesis and neural survival. The aim of this study was to investigate whether enriched olfactory stimuli affect neurogenesis of mitral and granule cells of the olfactory bulb and dentate gyrus, and whether respiratory activity accompanied by olfactory stimuli is associated with new cells in these regions. To this end, respiratory activity during enriched odor stimuli was continuously measured in mice and new cells were stained with 5-bromo-2'-deoxyuridine, which selectively labels proliferating cells. An enriched olfactory environment significantly increased neurogenesis of mitral and granule cells in the olfactory bulb, but not in the dentate gyrus. Additionally, an increase of new granule cells under the enriched odor condition was correlated to sniffing frequency power, which had a significantly different pattern from the no-odor condition. A high respiratory frequency with frequent odor stimuli may be associated with activation of granule cells to form inhibitory neurons and this active state might increase granule cell neurogenesis.


Neurons , Olfactory Bulb , Animals , Mice , Neurogenesis/physiology , Neurons/physiology , Odorants , Smell/physiology
12.
Sci Rep ; 12(1): 1589, 2022 01 31.
Article En | MEDLINE | ID: mdl-35102254

Electronic devices have become an indispensable part of our daily lives, while their negative aspects have been reported. One disadvantage is that reading comprehension is reduced when reading from an electronic device; the cause of this deficit in performance is unclear. In this study, we investigated the cause for comprehension decline when reading on a smartphone by simultaneously measuring respiration and brain activity during reading in 34 healthy individuals. We found that, compared to reading on a paper medium, reading on a smartphone elicits fewer sighs, promotes brain overactivity in the prefrontal cortex, and results in reduced comprehension. Furthermore, reading on a smartphone affected sigh frequency but not normal breathing, suggesting that normal breathing and sigh generation are mediated by pathways differentially influenced by the visual environment. A path analysis suggests that the interactive relationship between sigh inhibition and overactivity in the prefrontal cortex causes comprehension decline. These findings provide new insight into the respiration-mediated mechanisms of cognitive function.


Reading
13.
J Alzheimers Dis ; 85(2): 851-862, 2022.
Article En | MEDLINE | ID: mdl-34864676

BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is often misdiagnosed as Alzheimer's disease (AD) due to overlapping pathophysiology and similar imaging characteristics, including ventricular enlargement and increased white matter lesions (WMLs). OBJECTIVE: To compare the extent and distribution of WMLs directly between iNPH and AD and examine the association with underlying pathophysiology. METHODS: Twelve patients with iNPH (mean age: 78.08 years; 5 females), 20 with AD (mean age: 75.40 years; 13 females), and 10 normal cognition (NC) participants (mean age: 76.60 years; 7 females) were recruited. The extent and distribution of WMLs and the lateral ventricular volume (LV-V) were evaluated on MRI using voxel-based morphometry analysis. Concentrations of cerebrospinal fluid biomarkers, such as amyloid-ß protein (Aß)42, Aß40, Aß38, and tau species, were also measured. Risk factors for small vessel disease (SVD) were assessed by blood examination and medical records. RESULTS: The periventricular WML volume (PWML-V) and deep WML volume (DWML-V) were significantly larger in iNPH than in AD and NC. The DWML-V was dominant in iNPH, while the PWML-V was dominant in AD and NC. GM-V was significantly smaller in AD than in iNPH and NC. The LV-V positively correlated with WML-V in all participants. There was a significant negative correlation between LV-V and Aß38 in iNPH. Furthermore, there was no significant difference in SVD risk factors between the groups. CONCLUSION: The differences in the extent and distribution of WMLs between iNPH and AD, especially predominance of DWML-V over PWML-V in iNPH, may reflect decreased fluid and Aß clearance.


Alzheimer Disease/pathology , Hydrocephalus, Normal Pressure/pathology , White Matter/pathology , Aged , Aged, 80 and over , Alzheimer Disease/cerebrospinal fluid , Amyloid beta-Peptides/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Diagnosis, Differential , Female , Humans , Hydrocephalus, Normal Pressure/cerebrospinal fluid , Male , Middle Aged , Peptide Fragments/cerebrospinal fluid , tau Proteins/cerebrospinal fluid
14.
BMC Neurosci ; 22(1): 75, 2021 12 07.
Article En | MEDLINE | ID: mdl-34876001

BACKGROUND: Cognitive function declines with age and has been shown to be associated with atrophy in some brain regions, including the prefrontal cortex. However, the details of the relationship between aging and cognitive dysfunction are not well understood. METHODS: Across a wide range of ages (24- to 85-years-old), this research measured the gray matter volume of structural magnetic resonance imaging data in 39 participants, while some brain regions were set as mediator variables to assess the cascade process between aging and cognitive dysfunction in a path analysis. RESULTS: Path analysis showed that age affected the left hippocampus, thereby directly affecting the left superior frontal gyrus. Furthermore, the gyrus directly affected higher order flexibility and maintenance abilities calculated as in the Wisconsin card sorting test, and the two abilities affected the assessment of general cognitive function. CONCLUSION: Our finding suggests that a cascade process mediated by the left hippocampus and left superior frontal gyrus is involved in the relationship between aging and cognitive dysfunction.


Cognition/physiology , Cognitive Dysfunction/physiopathology , Hippocampus/pathology , Temporal Lobe/pathology , Adult , Aged , Aging/physiology , Cerebral Cortex/pathology , Cerebral Cortex/physiopathology , Cognitive Dysfunction/pathology , Hippocampus/physiopathology , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Temporal Lobe/physiopathology , Young Adult
15.
Brain Res Bull ; 177: 129-142, 2021 12.
Article En | MEDLINE | ID: mdl-34563634

There has been a long-standing controversy regarding the physiological role of serotonin (5-HT) neurons in the dorsal raphe nucleus (DRN) in sleep/wake architecture. Some studies have reported that 5-HT acts as a sleep-promoting agent, but several studies have suggested that DRN 5-HT neurons function predominantly to promote wakefulness and inhibit rapid eye movement (REM) sleep. Furthermore, recent studies have reported that there is a clear neurobiological difference between a waking state that includes alertness and active exploration (i.e., active wakefulness) and a waking state that is devoid of locomotion (i.e., quiet wakefulness). These states have also been shown to differ clinically in terms of memory consolidation. However, the effects of 5-HT neurons on the regulation of these two different waking states have not been fully elucidated. In the present study, we attempted to examine the physiological role of DRN 5-HT neurons in various sleep/wake states using optogenetic methods that allowed manipulation of cell-type specific neuronal activation with high temporal and anatomical precision. We crossed TPH2-tTA and TetO-ChR2(C128S) mice to obtain mice with channelrhodopsin-2 (ChR2) [C128S]-expressing central 5-HT neurons, and we activated DRN-5HT neurons or medullary 5-HT neurons. Optogenetic activation of DRN 5-HT neurons caused rapid transition from non-REM sleep to active wakefulness, not quiet wakefulness, whereas activation of medullary 5-HT neurons did not appear to affect sleep/wake states or locomotor activity. Our results may shed light on the physiological role of DRN 5-HT neurons in sleep/wake architecture and encourage further investigations of the cortical functional connectivity involved in sleep/wake state regulation.


Dorsal Raphe Nucleus , Wakefulness , Animals , Mice , Neurons/physiology , Optogenetics , Serotonin/physiology , Sleep
16.
Front Neurosci ; 15: 709050, 2021.
Article En | MEDLINE | ID: mdl-34413723

Specific odors can induce memories of the past, especially those associated with autobiographical and episodic memory. Odors associated with autobiographical memories have been found to elicit stronger activation in the orbitofrontal cortex, hippocampus, and parahippocampus compared with odors not linked to personal memories. Here, we examined whether continuous odor stimuli associated with autobiographical memories could activate the above olfactory areas in older adults and speculated regarding whether this odor stimulation could have a protective effect against age-related cognitive decline. Specifically, we used functional magnetic resonance imaging to investigate the relationship between blood oxygen levels in olfactory regions and odor-induced subjective memory retrieval and emotions associated with autobiographical memory in older adults. In our group of healthy older adults, the tested odors induced autobiographical memories that were accompanied by increasing levels of retrieval and the feeling of being "brought back in time." The strength of the subjective feelings, including vividness of the memory and degree of comfort, impacted activation of the left fusiform gyrus and left posterior orbitofrontal cortex. Further, our path model suggested that the strength of memory retrieval and of the emotions induced by odor-evoked autobiographical memories directly influenced neural changes in the left fusiform gyrus, and impacted left posterior orbitofrontal cortex activation through the left fusiform response.

17.
PLoS One ; 16(7): e0254623, 2021.
Article En | MEDLINE | ID: mdl-34293003

Emotion recognition is known to change with age, but associations between the change and brain atrophy are not well understood. In the current study atrophied brain regions associated with emotion recognition were investigated in elderly and younger participants. Group comparison showed no difference in emotion recognition score, while the score was associated with years of education, not age. We measured the gray matter volume of 18 regions of interest including the bilateral precuneus, supramarginal gyrus, orbital gyrus, straight gyrus, superior temporal sulcus, inferior frontal gyrus, insular cortex, amygdala, and hippocampus, which have been associated with social function and emotion recognition. Brain reductions were observed in elderly group except left inferior frontal gyrus, left straight gyrus, right orbital gyrus, right inferior frontal gyrus, and right supramarginal gyrus. Path analysis was performed using the following variables: age, years of education, emotion recognition score, and the 5 regions that were not different between the groups. The analysis revealed that years of education were associated with volumes of the right orbital gyrus, right inferior frontal gyrus, and right supramarginal gyrus. Furthermore, the right supramarginal gyrus volume was associated with the emotion recognition score. These results suggest that the amount of education received contributes to maintain the right supramarginal gyrus volume, and indirectly affects emotion recognition ability.


Emotions/physiology , Magnetic Resonance Imaging , Parietal Lobe/diagnostic imaging , Parietal Lobe/physiology , Adult , Aged , Aged, 80 and over , Brain Mapping , Female , Humans , Male , Middle Aged
18.
Front Neurosci ; 15: 648814, 2021.
Article En | MEDLINE | ID: mdl-33815049

Although animal studies and studies on Parkinson's disease (PD) suggest that dopamine deficiency slows the pace of the internal clock, which is corrected by dopaminergic medication, timing deficits in parkinsonism remain to be characterized with diverse findings. Here we studied patients with PD and progressive supranuclear palsy (PSP), 3-4 h after drug intake, and normal age-matched subjects. We contrasted perceptual (temporal bisection, duration comparison) and motor timing tasks (time production/reproduction) in supra- and sub-second time domains, and automatic versus cognitive/short-term memory-related tasks. Subjects were allowed to count during supra-second production and reproduction tasks. In the time production task, linearly correlating the produced time with the instructed time showed that the "subjective sense" of 1 s is slightly longer in PD and shorter in PSP than in normals. This was superposed on a prominent trend of underestimation of longer (supra-second) durations, common to all groups, suggesting that the pace of the internal clock changed from fast to slow as time went by. In the time reproduction task, PD and, more prominently, PSP patients over-reproduced shorter durations and under-reproduced longer durations at extremes of the time range studied, with intermediate durations reproduced veridically, with a shallower slope of linear correlation between the presented and produced time. In the duration comparison task, PD patients overestimated the second presented duration relative to the first with shorter but not longer standard durations. In the bisection task, PD and PSP patients estimated the bisection point (BP50) between the two supra-second but not sub-second standards to be longer than normal subjects. Thus, perceptual timing tasks showed changes in opposite directions to motor timing tasks: underestimating shorter durations and overestimating longer durations. In PD, correlation of the mini-mental state examination score with supra-second BP50 and the slope of linear correlation in the reproduction task suggested involvement of short-term memory in these tasks. Dopamine deficiency didn't correlate significantly with timing performances, suggesting that the slowed clock hypothesis cannot explain the entire results. Timing performance in PD may be determined by complex interactions among time scales on the motor and sensory sides, and by their distortion in memory.

19.
Brain Behav ; 11(5): e02115, 2021 05.
Article En | MEDLINE | ID: mdl-33769719

INTRODUCTION: Pathological abnormalities first appear in the medial temporal regions including entorhinal cortex and parahippocampus in patients with Alzheimer's disease. Previous studies showed that olfactory decline in elderly subjects was associated with volume reductions in the left hippocampus and left parahippocampus without cognitive impairment. The aim of this study is to investigate the link between olfaction and volume reductions in the medial temporal regions including the parahippocampus, entorhinal cortex, and hippocampal subfields. METHOD: 27 elderly subjects and 27 young controls were measured olfaction acuity, cognitive function, and structural magnetic resonance imaging. Image processing and gray matter volumetric segmentation were performed with FreeSurfer. Volume data were analyzed with SPSS Statistics software. RESULTS: Interesting results of this study were that volume reduction in the entorhinal cortex was not directly linked with declining olfactory ability. Volume reduction in the left entorhinal cortex was correlated with volume reduction in the left parahippocampus and dentate gyrus. However, left parahippocampus volume reduction had the greatest impact on olfactory decline, and the entorhinal cortex and dentate gyrus might additionally contribute to olfactory decline. CONCLUSION: Our results indicate that olfactory decline may be directly reflected in the medial temporal regions as reduced parahippocampus volumes, rather than as morphological changes in the entorhinal cortex and hippocampus. The parahippocampus may play an important role in the association between memory retrieval and olfactory identification.


Entorhinal Cortex , Smell , Aged , Hippocampus/diagnostic imaging , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging
20.
J Neurosci Res ; 99(5): 1325-1336, 2021 05.
Article En | MEDLINE | ID: mdl-33594677

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.


Cognition/physiology , Parkinson Disease/psychology , Parkinson Disease/therapy , Reaction Time/physiology , Space Perception/physiology , Time Perception/physiology , Acoustic Stimulation/methods , Aged , Female , Humans , Male , Neuropsychological Tests , Random Allocation
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