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1.
Gan To Kagaku Ryoho ; 51(4): 448-450, 2024 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-38644318

RESUMEN

This patient visited our hospital for the purpose of detailed examination of prostate cancer in his seventies. Abdominal contrast-enhanced computed tomography(CT)revealed a low-density mass of 2 cm in the pancreatic head. He was diagnosed with pancreatic cancer. Pancreaticoduodenectomy was performed after 2 courses of gemcitabine and S-1 therapy were performed as neoadjuvant chemotherapy. An intraoperative clamp test of the gastroduodenal artery showed that the pulsation of the common hepatic artery and the proper hepatic artery was weak but sufficient, so the gastroduodenal artery was cut and the operation was completed as planned. A blood test on the 1st day after the operation showed elevated levels of AST 537 U/L, ALT 616 U/L, and 7 hours later blood sampling showed further increases in AST 1,455 U/L, ALT 1,314 U/L. After a detailed review of the preoperative CT, celiac artery stenosis due to compression of the arcuate ligament was suspected, and urgent median arcuate ligament release was performed on the same day. Dissection of the arcuate ligament significantly improved the pulsation of the common hepatic artery and proper hepatic artery. Postoperatively, hepatic enzymes improved and ISGPS showed Grade B pancreatic juice leakage, but the patient was discharged from the hospital on the 49th postoperative day without any other complications. He took S-1 as adjuvant chemotherapy, and no signs of recurrence have been observed 9 months after the operation.


Asunto(s)
Adenocarcinoma , Arteria Celíaca , Neoplasias Pancreáticas , Pancreaticoduodenectomía , Humanos , Adenocarcinoma/cirugía , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Arteria Celíaca/cirugía , Constricción Patológica/cirugía , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Desoxicitidina/administración & dosificación , Combinación de Medicamentos , Gemcitabina , Síndrome del Ligamento Arcuato Medio/cirugía , Ácido Oxónico/uso terapéutico , Ácido Oxónico/administración & dosificación , Neoplasias Pancreáticas/cirugía , Tegafur/uso terapéutico , Tegafur/administración & dosificación
2.
PLoS One ; 18(5): e0285557, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37155637

RESUMEN

Driver drowsiness is a widely recognized cause of motor vehicle accidents. Therefore, a reduction in drowsy driving crashes is required. Many studies evaluating the crash risk of drowsy driving and developing drowsiness detection systems, have used observer rating of drowsiness (ORD) as a reference standard (i.e. ground truth) of drowsiness. ORD is a method of human raters evaluating the levels of driver drowsiness, by visually observing a driver. Despite the widespread use of ORD, concerns remain regarding its convergent validity, which is supported by the relationship between ORD and other drowsiness measures. The objective of the present study was to validate video-based ORD, by examining correlations between ORD levels and other drowsiness measures. Seventeen participants performed eight sessions of a simulated driving task, verbally responding to Karolinska sleepiness scale (KSS), while infra-red face video, lateral position of the participant's car, eye closure, electrooculography (EOG), and electroencephalography (EEG) were recorded. Three experienced raters evaluated the ORD levels by observing facial videos. The results showed significant positive correlations between the ORD levels and all other drowsiness measures (i.e., KSS, standard deviation of the lateral position of the car, percentage of time occupied by slow eye movement calculated from EOG, EEG alpha power, and EEG theta power). The results support the convergent validity of video-based ORD as a measure of driver drowsiness. This suggests that ORD might be suitable as a ground truth for drowsiness.


Asunto(s)
Conducción de Automóvil , Humanos , Somnolencia , Vigilia/fisiología , Accidentes de Tránsito , Movimientos Oculares , Electroencefalografía , Fases del Sueño/fisiología
3.
Gan To Kagaku Ryoho ; 50(3): 384-386, 2023 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-36927917

RESUMEN

A 98-year-old woman presented with hematochezia and a circumferential type 2 tumor in the rectum Rb identified on fiberoscopy. We a performed laparoscopic Hartmann's operation and D2 lymphadenectomy for advanced rectal cancer. A sigmoid colostomy was created via the intraperitoneal route. On the postoperative day 12, the patient experienced abdominal pain. Computed tomography showed that the small intestine formed a closed loop in the pelvic space. The patient was diagnosed with a strangulated bowel obstruction of the small intestine for which an emergency exploratory laparotomy was performed. The small intestine, which had passed through a defect between the lifted sigmoid colon and the left abdominal wall, was strangulated by the lifted sigmoid colon. We performed partial resection of the small intestine. The patient died on postoperative day 32 of acute deterioration of aortic valve stenosis. There have been few reports of strangulated bowel obstruction resulting from internal hernia associated with colostomy. These findings demonstrate that it is important to select the appropriate route for colostomy creation in each case.


Asunto(s)
Obstrucción Intestinal , Laparoscopía , Neoplasias del Recto , Femenino , Humanos , Anciano de 80 o más Años , Neoplasias del Recto/complicaciones , Neoplasias del Recto/cirugía , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Recto/cirugía , Colon Sigmoide/cirugía , Laparoscopía/métodos , Colostomía
4.
Gan To Kagaku Ryoho ; 49(13): 1811-1813, 2022 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-36733007

RESUMEN

A 79-year-old man visited the hospital because of constipation. Colonoscopy showed a transverse colon carcinoma. Dynamic CT showed a renal neoplastic lesion and 2 lesions in the liver with early staining and late wash out, and the liver lesions showed ring enhancement on EOB-MRI. The preoperative diagnosis was either transverse colon cancer, renal cell carcinoma, hepatocellular carcinoma, or metastatic liver cancer. The patient underwent partial transverse colon resection, partial right nephrectomy, and partial hepatic resection. Additional to the 2 liver lesions in S6, an intraoperative ultrasound showed 1 tumor in S5; therefore, 3 partial hepatectomies were performed. Histopathological findings revealed that the tumors in S5 and S6 were liver metastases of transverse colon cancer and renal cell carcinoma, respectively. The final diagnosis was transverse colon cancer, pT4a, pN0, pM1, pStage Ⅳa and papillary renal cell carcinoma, pT1a, pN0, pM1, pStage Ⅳ. For 9 months postoperatively, there was no apparent recurrence.


Asunto(s)
Carcinoma Hepatocelular , Carcinoma de Células Renales , Colon Transverso , Neoplasias del Colon , Neoplasias Renales , Neoplasias Hepáticas , Masculino , Humanos , Anciano , Carcinoma Hepatocelular/secundario , Neoplasias Hepáticas/secundario , Colon Transverso/cirugía , Carcinoma de Células Renales/cirugía , Neoplasias del Colon/cirugía , Neoplasias Renales/cirugía , Neoplasias Renales/patología
5.
Gan To Kagaku Ryoho ; 49(13): 1953-1955, 2022 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-36733055

RESUMEN

A 54-year-old woman visited to a doctor nearby medical clinic complaining of loss of appetite. She was diagnosed with right hydronephrosis on abdominal ultrasonography, and referred to our hospital for further examination. Contrast abdominal computed tomography(CT)revealed that a 6.2 cm tumor with a contrast-enhancing effect inside in the retroperitoneum near the lower pole of the right kidney. She was diagnosed with hydronephrosis due to infiltration of the right kidney of a retroperitoneal tumor. The tumor was suspected of invading the duodenum and inferior vena cava, but no obvious lymph node or distant metastasis was observed. Abdominal MRI revealed a tumor showed hyperintensity on T2-weighted and diffusion-weighted images. We performed pancreaticoduodenectomy with inferior vena cava resection and right nephrectomy. The pathological diagnosis was leiomyosarcoma originating from retroperitoneum and pT2, pN0, pM0, pStage ⅢA. The postoperative course was good, and she was discharged 10 days after the operation. Thoracoabdominal CT showed a tumor 4 cm at the hepatic hilum three months after surgery, and EOB-MRI showed many tumors other than the same site, so multiple liver metastases were diagnosed as recurrence. Doxorubicin has been started and is still being treated.


Asunto(s)
Hidronefrosis , Leiomiosarcoma , Neoplasias Hepáticas , Neoplasias Retroperitoneales , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Retroperitoneales/diagnóstico por imagen , Neoplasias Retroperitoneales/cirugía , Neoplasias Retroperitoneales/patología , Pancreaticoduodenectomía , Leiomiosarcoma/diagnóstico por imagen , Leiomiosarcoma/cirugía , Leiomiosarcoma/irrigación sanguínea , Neoplasias Hepáticas/cirugía , Vena Cava Inferior/cirugía , Vena Cava Inferior/patología
6.
PLoS One ; 16(11): e0259243, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34735509

RESUMEN

Many older adults have difficulty seeing brief visual stimuli which younger adults can easily recognize. The primary visual cortex (V1) may induce this difficulty. However, in neuroimaging studies, the V1 response change to the increase of temporal frequency of visual stimulus in older adults was unclear. Here we investigated the association between the temporal frequency of flickering stimuli and the BOLD activity within V1 in older adults, using surface-based fMRI analysis. The fMRI data from 29 healthy older participants stimulated by contrast-reversing checkerboard at temporal flicker frequencies of 2, 4, and 8 Hz were obtained. The participants also performed a useful field of view (UFOV) test. The slope coefficient of BOLD activity regarding the temporal frequency of the visual stimulus averaged within V1 regions of interest was positive and significantly different from zero. Group analysis in the V1 showed significant clusters with positive slope and no significant clusters with a negative slope. The correlation coefficient between the slope coefficient and UFOV performance was not significant. The results indicated that V1 BOLD response to a flickering visual stimulus increases as the stimulus temporal frequency increases from 2 to 8 Hz in older adults.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Estimulación Luminosa/métodos , Corteza Visual Primaria/fisiología , Anciano , Femenino , Voluntarios Sanos , Humanos , Masculino
7.
Sci Rep ; 8(1): 711, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29335538

RESUMEN

Despite the ubiquity and importance of speeding offenses, there has been little neuroscience research regarding the propensity for speeding among vehicle drivers. In the current study, as a first attempt, we examined the hypothesis that visual inputs during high-speed driving would activate the mesolimbic dopaminergic system that plays an important role in mediating motivational craving. To this end, we used functional magnetic resonance imaging to identify speed-related activation changes in mesolimbic dopaminergic regions during the observation of driver-view videos in two groups that differed in self-reported speeding propensity. Results revealed, as we expected, greater activation in the ventral tegmental area (VTA) in response to driver-view videos with higher speed. Contrary to our expectation, however, we found no significant between-group difference in speed-related activation changes in mesolimbic dopaminergic regions. Instead, an exploratory psychophysiological interaction analysis found that self-reported speeding propensity was associated with speed-related functional coupling between the VTA and the right intraparietal sulcus. Further validation of our hypothesis will require future studies examining associations between speed-related activation in the mesolimbic dopaminergic system and individual differences in speeding propensity, using a more reliable measure of actual speeding propensity in real traffic.


Asunto(s)
Conducción de Automóvil , Neuronas Dopaminérgicas/fisiología , Lóbulo Parietal/fisiología , Estimulación Luminosa , Área Tegmental Ventral/fisiología , Adulto , Mapeo Encefálico , Femenino , Voluntarios Sanos , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
8.
Sci Rep ; 7: 46526, 2017 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-28417971

RESUMEN

Previous functional neuroimaging studies have identified multiple brain areas associated with distinct aspects of car driving in simulated traffic environments. Few studies, however, have examined brain morphology associated with everyday car-driving experience in real traffic. Thus, the aim of the current study was to identify gray matter volume differences between drivers and non-drivers. We collected T1-weighted structural brain images from 73 healthy young adults (36 drivers and 37 non-drivers). We performed a whole-brain voxel-based morphometry analysis to examine between-group differences in regional gray matter volume. Compared with non-drivers, drivers showed significantly greater gray matter volume in the left cerebellar hemisphere, which has been associated with cognitive rather than motor functioning. In contrast, we found no brain areas with significantly greater gray matter volume in non-drivers compared with drivers. Our findings indicate that experience with everyday car driving in real traffic is associated with greater gray matter volume in the left cerebellar hemisphere. This brain area may be involved in abilities that are critical for driving a car, but are not commonly or frequently used during other daily activities.


Asunto(s)
Conducción de Automóvil , Cerebelo , Sustancia Gris , Imagen por Resonancia Magnética , Adulto , Mapeo Encefálico , Cerebelo/diagnóstico por imagen , Cerebelo/fisiología , Femenino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/fisiología , Humanos , Masculino
9.
BMC Geriatr ; 17(1): 96, 2017 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-28446144

RESUMEN

BACKGROUND: Older people are at greater risk of traffic accidents, partially because of age-related declines in visual function, including reduced useful field of view (UFOV). However, lifestyle factors which cause age-related decline in UFOV remain poorly understood. We conducted a study to investigate whether physical activity and appetite status were related to UFOV test performance in healthy older adults. METHODS: Thirty community-dwelling older people (age 68.6 ± 3.1 years, 15 females) were enrolled in this study. Each participant completed the Council on Nutrition appetite questionnaire (CNAQ) and a UFOV test. They then wore a tri-axial accelerometer (Active style Pro HJA-350IT) for 3-6 consecutive days to objectively measure their PA in free-living conditions. RESULTS: Longer time spent in vigorous physical activity was significantly associated with better UFOV test performance when adjusted for age and accelerometer wear time (non-locomotive: r = -0.435, locomotive: r = -0.449; n = 25). In addition, male, but not female, participants with a higher CNAQ score had significantly better UFOV test performance in both an unadjusted model (r = -0.560; n = 15) and a model adjusted for age (r = -0.635; n = 15). CONCLUSIONS: The results suggest that appetite status among males and time spent in high intensity PA are associated with visual function related to driving competence in older adults.


Asunto(s)
Apetito/fisiología , Conducción de Automóvil/psicología , Ejercicio Físico/fisiología , Ejercicio Físico/psicología , Desempeño Psicomotor/fisiología , Percepción Visual/fisiología , Accidentes de Tránsito/prevención & control , Accidentes de Tránsito/psicología , Anciano , Anciano de 80 o más Años , Conducción de Automóvil/normas , Femenino , Humanos , Masculino , Estimulación Luminosa/métodos , Encuestas y Cuestionarios
10.
Geriatr Gerontol Int ; 15(5): 659-65, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25110186

RESUMEN

AIM: Although age-related decline in the useful field of view (UFOV) is well recognized as a risk factor for at-fault crash involvement in elderly drivers, there is still room to study its applicability to elderly Japanese drivers. In the current study, we thus examined the relationship between UFOV and at-fault crash history in an elderly Japanese population. We also explored whether potential factors that create awareness of reduced driving fitness could be a trigger for the self-regulation of driving in elderly drivers. METHODS: We measured UFOV and at-fault crash history from 151 community-dwelling Japanese aged 60 years or older, and compared UFOV of at-fault crash-free and crash-involved drivers. We also measured self-evaluated driving style using a questionnaire. RESULTS: UFOV in crash-involved drivers was significantly lower than that in crash-free drivers. No significant difference was found in self-evaluated driving style between crash-free and crash-involved drivers. In addition, there was no significant association between UFOV and self-evaluated driving style. CONCLUSIONS: The present study showed that UFOV is a good predictor of at-fault crash risk in elderly Japanese drivers. Furthermore, our data imply that it might be difficult for elderly drivers to adopt appropriate driving strategies commensurate with their current driving competence.


Asunto(s)
Accidentes de Tránsito , Pruebas del Campo Visual , Anciano , Pueblo Asiatico , Conducción de Automóvil , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas
11.
Behav Brain Res ; 273: 57-62, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25084042

RESUMEN

Noninvasive brain stimulation techniques have increasingly attracted the attention of neuroscientists because they enable the identification of the causal role of a targeted brain region. However, few studies have applied such techniques to everyday life situations. Here, we investigate the causal role of the dorsolateral prefrontal cortex (DLPFC) in fundamental vehicle control abilities. Thirteen participants underwent a simulated driving task under prefrontal transcranial direct current stimulation (tDCS) on three separate testing days. Each testing day was randomly assigned to either anodal over the right with cathodal over the left DLPFC, cathodal over the right with anodal over the left DLPFC, or sham stimulation. The driving task required the participants to maintain an inter-vehicle distance to a leading car traveling a winding road with a constant speed. Driving performance was quantified using two metrics: the root-mean-square error of inter-vehicle distance as car-following performance, and the standard deviation of lateral position as lane-keeping performance. Results showed that both car-following and lane-keeping performances were significantly greater for right anodal/left cathodal compared with right cathodal/left cathodal and sham stimulation. These results suggest not only the causal involvement of the DLPFC in driving, but also right hemisphere dominance for vehicle control. The findings of this study indicate that tDCS can be a useful tool to examine the causal role of a specific brain region in ecologically valid environments, and also might be a help to drivers with difficulties in vehicle control.


Asunto(s)
Conducción de Automóvil , Corteza Prefrontal/fisiología , Estimulación Transcraneal de Corriente Directa , Adulto , Femenino , Lateralidad Funcional , Humanos , Masculino
12.
PLoS One ; 8(6): e67391, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23825657

RESUMEN

Humans can anticipate and prepare for uncertainties to achieve a goal. However, it is difficult to maintain this effort over a prolonged period of time. Inappropriate behavior is impulsively (or mindlessly) activated by an external trigger, which can result in serious consequences such as traffic crashes. Thus, we examined the neural mechanisms underlying such impulsive responding using functional magnetic resonance imaging (fMRI). Twenty-two participants performed a block-designed sustained attention to response task (SART), where each task block was composed of consecutive Go trials followed by a NoGo trial at the end. This task configuration enabled us to measure compromised preparation for NoGo trials during Go responses using reduced Go reaction times. Accordingly, parametric modulation analysis was conducted on fMRI data using block-based mean Go reaction times as an online marker of impulsive responding in the SART. We found that activity in the right dorsolateral prefrontal cortex (DLPFC) and the bilateral intraparietal sulcus (IPS) was positively modulated with mean Go reaction times. In addition, activity in the medial prefrontal cortex (MPFC) and the posterior cingulate cortex (PCC) was negatively modulated with mean Go reaction times, albeit statistically weakly. Taken together, spontaneously reduced activity in the right DLPFC and the IPS and spontaneously elevated activity in the MPFC and the PCC were associated with impulsive responding in the SART. These results suggest that such a spontaneous transition of brain activity pattern results in impulsive responding in monotonous situations, which in turn, might cause human errors in actual work environments.


Asunto(s)
Atención/fisiología , Encéfalo/fisiopatología , Conducta Impulsiva/fisiopatología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Tiempo de Reacción
13.
PLoS One ; 7(9): e45920, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23029316

RESUMEN

Although low executive functioning is a risk factor for vehicle crashes among elderly drivers, the neural basis of individual differences in this cognitive ability remains largely unknown. Here we aimed to examine regional frontal gray matter volume associated with executive functioning in normal aging individuals, using voxel-based morphometry (VBM). To this end, 39 community-dwelling elderly volunteers who drove a car on a daily basis participated in structural magnetic resonance imaging, and completed two questionnaires concerning executive functioning and risky driving tendencies in daily living. Consequently, we found that participants with low executive function capacity were prone to risky driving. Furthermore, VBM analysis revealed that lower executive function capacity was associated with smaller gray matter volume in the supplementary motor area (SMA). Thus, the current data suggest that SMA volume is a reliable predictor of individual differences in executive function capacity as a risk factor for vehicle crashes among elderly persons. The implication of our results is that regional frontal gray matter volume might underlie the variation in driving tendencies among elderly drivers. Therefore, detailed driving behavior assessments might be able to detect early neurodegenerative changes in the frontal lobe in normal aging adults.


Asunto(s)
Accidentes de Tránsito/psicología , Envejecimiento , Conducción de Automóvil/psicología , Función Ejecutiva , Lóbulo Frontal/anatomía & histología , Lóbulo Frontal/fisiología , Anciano , Femenino , Humanos , Masculino , Tamaño de los Órganos , Encuestas y Cuestionarios
14.
Ergonomics ; 55(7): 743-51, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22506809

RESUMEN

Alerting drivers for self-regulation of attention might decrease crash risks attributable to absent-minded driving. However, no reliable method exists for monitoring driver attention. Therefore, we examined attentional effects on gaze preference for salient loci (GPS) in traffic scenes. In an active viewing (AV) condition requiring endogenous attention for traffic scene comprehension, participants identified appropriate speeds for driving in presented traffic scene images. In a passive viewing (PV) condition requiring no endogenous attention, participants passively viewed traffic scene images. GPS was quantified by the mean saliency value averaged across fixation locations. Results show that GPS was less during AV than during PV. Additionally, gaze dwell time on signboards was shorter for AV than for PV. These results suggest that, in the absence of endogenous attention for traffic scene comprehension, gaze tends to concentrate on irrelevant salient loci in a traffic environment. Therefore, increased GPS can indicate absent-minded driving. PRACTITIONER SUMMARY: The present study demonstrated that, without endogenous attention for traffic scene comprehension, gaze tends to concentrate on irrelevant salient loci in a traffic environment. This result suggests that increased gaze preference for salient loci indicates absent-minded driving, which is otherwise difficult to detect.


Asunto(s)
Atención/fisiología , Conducción de Automóvil/psicología , Reconocimiento Visual de Modelos/fisiología , Accidentes de Tránsito , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Psicometría , Tiempo de Reacción , Autoinforme , Percepción Visual/fisiología
15.
Ergonomics ; 54(2): 146-53, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21294012

RESUMEN

In recently developed intelligent vehicles, warning alarms are often used to prompt avoidance behaviours from drivers facing imminent hazardous situations. However, when critical reaction delays to auditory stimulation are anticipated, the alarm should be activated earlier to compensate for such delays. It was found that reaction times to an auditory stimulus significantly increased in the presence of slow eye movement (SEM), which is known to occur frequently during the wake-sleep transition. The reaction delay could not be attributed to temporal effects such as fatigue and was invariant regardless of response effectors (finger or foot). Moreover, it was found that applied pedal force decreased immediately after an auditory stimulus interrupted SEM. Consequently, it was concluded that SEM can be a good predictor of reaction delays to auditory warning alarms when drivers are in a drowsy state. STATEMENT OF RELEVANCE: The present study demonstrated that simple auditory reaction time significantly increased when SEM emerged. In the design of vehicle safety systems using warning alarms to prompt avoidance behaviours from drivers, such reaction delays during SEM must be taken into account.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Cognición/fisiología , Movimientos Oculares/fisiología , Tiempo de Reacción/fisiología , Vigilia/fisiología , Adulto , Análisis de Varianza , Ergonomía , Femenino , Humanos , Masculino , Factores de Tiempo
16.
J Sleep Res ; 20(3): 416-24, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21070424

RESUMEN

A delayed response caused by sleepiness can result in severe car accidents. Previous studies suggest that slow eye movement (SEM) is a sleep-onset index related to delayed response. This study was undertaken to verify that SEM detection is effective for preventing sleep-related accidents. We propose a real-time detection algorithm of SEM based on feature-extracted parameters of electrooculogram (EOG), i.e. amplitude and mean velocity of eye movement. In Experiment 1, 12 participants (33.5 ± 7.3 years) performed an auditory detection task with EOG measurement to determine the threshold parameters of the proposed algorithm. Consequently, the valid threshold parameters were determined, respectively, as >5° and <30° s(-1) . In Experiment 2, 11 participants (32.8 ± 7.2 years) performed a simulated car-following task to verify that the SEM detection is effective for preventing sleep-related accidents. Accidents in the SEM condition were significantly more numerous than in the non-SEM condition (P < 0.01, one-way repeated-measures anova followed by Scheffé's test). Furthermore, no accident occurred in the SEM condition with a warning generated using the proposed algorithm. Results also demonstrate clearly that the SEM detection can prevent sleep-related accidents effectively in this simulated driving task.


Asunto(s)
Accidentes de Tránsito/prevención & control , Conducción de Automóvil/psicología , Medidas del Movimiento Ocular , Privación de Sueño/psicología , Accidentes de Tránsito/psicología , Adulto , Algoritmos , Electrooculografía , Movimientos Oculares/fisiología , Femenino , Humanos , Masculino , Privación de Sueño/fisiopatología
17.
Neurosci Res ; 68(1): 51-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20561955

RESUMEN

The "warning effect" refers to the decrease in motor response reaction times to a target when its presentation is preceded by a stimulus indicating that the target will appear shortly. We hypothesized that cue presentation phasically enhances alertness, which in turn facilitates the preparation of a motor response. To test this hypothesis, we conducted functional magnetic resonance imaging during a Go/NoGo task with a warning stimulus. Fifteen subjects completed a visual Go/NoGo task, and 12 completed an analogous task in the auditory modality. After a warning stimulus was presented, a Go or NoGo stimulus was presented with equal probability. Both auditory and visual warning stimuli activated the midbrain, thalamus, and the anterior cingulate cortex (ACC) extending to the pre-supplementary motor area (pre-SMA). The warning-related activation in the pre-SMA and thalamus was greater when warnings were followed by Go events with faster reaction times than when followed by events with slower reaction times. The midbrain, thalamus, and ACC are known to be associated with vigilance or intrinsic alertness, and the pre-SMA is involved in movement selection and preparation. Thus, the warning effect may be partly mediated by the potentiation of the pre-SMA through the midbrain-thalamus-ACC alerting network.


Asunto(s)
Nivel de Alerta/fisiología , Atención/fisiología , Encéfalo/fisiología , Movimiento/fisiología , Red Nerviosa/fisiología , Desempeño Psicomotor/fisiología , Adulto , Encéfalo/anatomía & histología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Vías Nerviosas/fisiología , Adulto Joven
18.
Hum Psychopharmacol ; 25(3): 260-7, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20373478

RESUMEN

OBJECTIVE: To assess the effects of two anxiolytics, diazepam and tandospirone, on driving performance from methodological viewpoints taking frequent rear-end collisions into account. METHODS: In this double-blinded, three-way crossover trial, 18 healthy males received acute doses of 20 mg tandospirone (TSP), 5 mg diazepam (DZP), and placebo (PCB). The subjects were administered three driving tasks-road tracking, car following, and harsh braking-performed using a driving simulator and three cognitive tasks-Wisconsin Card Sorting Test, Continuous Performance Test, and N-back test-at baseline and at 1 and 4 h post-dosing. The Stanford Sleepiness Scale scores were also assessed. RESULTS: DZP nonsignificantly increased the percent change of brake reaction time (BRT) as compared to PCB at 4 h post-dosing. TSP nonsignificantly decreased the percent change of BRT as compared to PCB. Consequently, there was a significant difference in the percent change of BRT between DZP and TSP at 4 h post-dosing. For the remaining tasks, no statistically significant effects of treatment were observed. CONCLUSIONS: Acute doses of DZP significantly impaired the harsh-braking performance as compared to acute doses of TSP. These findings suggest that TSP may be used more safely in patients' driving activities.


Asunto(s)
Conducción de Automóvil , Cognición/efectos de los fármacos , Diazepam/administración & dosificación , Isoindoles/administración & dosificación , Piperazinas/administración & dosificación , Desempeño Psicomotor/efectos de los fármacos , Pirimidinas/administración & dosificación , Adulto , Conducción de Automóvil/psicología , Cognición/fisiología , Estudios Cruzados , Diazepam/efectos adversos , Método Doble Ciego , Humanos , Isoindoles/efectos adversos , Masculino , Piperazinas/efectos adversos , Desempeño Psicomotor/fisiología , Pirimidinas/efectos adversos , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología , Factores de Tiempo
19.
Psychiatry Clin Neurosci ; 62(5): 610-6, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18950383

RESUMEN

AIMS: Amitriptyline triggers the impairment of cognitive and motor functions and has been confirmed to have harmful effects on driving performance. Although interindividual differences in plasma concentration may cause variations in driving performance, the relationship between plasma amitriptyline concentration and its effect on driving performance has not been completely elucidated. Thus, the aim of the present study was to assess the influence of individual pharmacokinetic differences on driving performance and cognitive functions. METHODS: In this double-blinded study, 17 healthy male volunteers were given an acute, single, 25-mg dose of amitriptyline. The subjects were assigned three driving simulator tasks, three cognitive tasks, and the questionnaire of the Stanford Sleepiness Scale at the baseline and at 4 h after dosing. The plasma amitriptyline concentrations were measured on high-performance liquid chromatography. RESULTS: A significant positive correlation was observed between the plasma amitriptyline concentration and road-tracking performance (r = 0.543, P < 0.05). There was no significant correlation between the plasma amitriptyline concentration and other driving performance, cognitive functions, and subjective somnolence. CONCLUSIONS: Amitriptyline produces a concentration-related impairment on road-tracking performance. Therapeutic monitoring of amitriptyline would be useful for predicting the difficulties involved while driving.


Asunto(s)
Amitriptilina/farmacocinética , Antidepresivos Tricíclicos/farmacocinética , Conducción de Automóvil , Desempeño Psicomotor/efectos de los fármacos , Adulto , Amitriptilina/farmacología , Antidepresivos Tricíclicos/farmacología , Nivel de Alerta/efectos de los fármacos , Atención/efectos de los fármacos , Simulación por Computador , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Humanos , Masculino , Pruebas Neuropsicológicas
20.
Neurosci Res ; 61(3): 309-18, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18457890

RESUMEN

We used functional magnetic resonance imaging in 18 normal volunteers to determine whether there is separate representation of syntactic, semantic, and verbal working memory processing in the left inferior frontal gyrus (GFi). We compared a sentence comprehension task with a short-term memory maintenance task to identify syntactic and semantic processing regions. To investigate the effects of syntactic and verbal working memory load while minimizing the differences in semantic processes, we used comprehension tasks with garden-path (GP) sentences, which require re-parsing, and non-garden-path (NGP) sentences. Compared with the short-term memory task, sentence comprehension activated the left GFi, including Brodmann areas (BAs) 44, 45, and 47, and the left superior temporal gyrus. In GP versus NGP sentences, there was greater activity in the left BAs 44, 45, and 46 extending to the left anterior insula, the pre-supplementary motor area, and the right cerebellum. In the left GFi, verbal working memory activity was located more dorsally (BA 44/45), semantic processing was located more ventrally (BA 47), and syntactic processing was located in between (BA 45). These findings indicate a close relationship between semantic and syntactic processes, and suggest that BA 45 might link verbal working memory and semantic processing via syntactic unification processes.


Asunto(s)
Mapeo Encefálico , Lóbulo Frontal/irrigación sanguínea , Lóbulo Frontal/fisiología , Lenguaje , Imagen por Resonancia Magnética , Memoria a Corto Plazo/fisiología , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Pruebas Neuropsicológicas , Oxígeno/sangre , Tiempo de Reacción/fisiología , Conducta Verbal/fisiología
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