Reduced prefrontal hemodynamic response in adult attention-deficit hyperactivity disorder as measured by near-infrared spectroscopy.

AIM: Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders. In pediatric attention-deficit hyperactivity disorder (ADHD), reduced prefrontal hemodynamic responses have been observed with NIRS repeatedly. However, there are few studies of adult ADHD by multi-channel NIRS. Therefore, in this study, we used multi-channel NIRS to examine the characteristics of prefrontal hemodynamic responses during the Stroop Color-Word Task (SCWT) in adult ADHD patients and in age- and sex-matched control subjects. METHODS: Twelve treatment-naïve adults with ADHD and 12 age- and sex-matched healthy control subjects participated in the present study after giving consent. We used 24-channel NIRS to measure the oxygenated hemoglobin (oxy-Hb) changes at the frontal lobes of participants during the SCWT. We compared the oxy-Hb changes between adults with ADHD and control subjects by t-tests with Bonferroni correction. RESULTS: During the SCWT, the oxy-Hb changes observed in the ADHD group were significantly smaller than those in the control group in channels 11, 16, 18, 21, 22, 23, and 24, corresponding to the prefrontal cortex. At channels 16, 21, 23, and 24 of the ADHD group, there were negative correlations between the symptomatic severity and the oxy-Hb changes. CONCLUSION: The present study suggests that adults with ADHD have reduced prefrontal hemodynamic response as measured by NIRS.

Pharmacotherapy for the treatment of aggression in pediatric and adolescent patients with autism spectrum disorder comorbid with attention-deficit hyperactivity disorder: A questionnaire survey of 571 psychiatrists.

AIM: Both attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are frequently accompanied by serious aggression that requires psychiatric treatment. However, little is known about the experiences psychiatrists have had using pharmacotherapy to treat aggression in patients who have both ASD and ADHD (ASD/ADHD). The purpose of this study was to examine the experiences of Japanese child and adolescent psychiatrists in prescribing medication for aggression in patients with ASD/ADHD. METHODS: A prospective questionnaire was mailed to 2001 psychiatrists affiliated with the Japanese Society for Child and Adolescent Psychiatry. Multivariate logistic regression analysis was used to identify factors predicting the outcome of pharmacotherapeutic treatment of aggression in pediatric and adolescent patients with ASD/ADHD. RESULTS: Of 2001 psychiatrists, 571 (28.5%) completed the full questionnaire (final sample). Of these, 488 (85.4%) prescribed psychotropic medication in treating pediatric and adolescent patients with ASD/ADHD, 299 (61.3%) of them doing so to treat aggression. Prescribers' duration of practice (odds ratio, 1.055; P = 0.038) and patient symptoms of residual impulsivity (odds ratio, 2.479; P = 0.039) increased the odds of prescribing psychotropic medications to treat aggression in these patients. The respondents reported a similar effect for patients with ADHD/ASD compared with those with ADHD only in treating aggression. CONCLUSION: Japanese psychiatrists tended to prescribe psychotropic medication for aggression in pediatric and adolescent patients with ASD/ADHD. Future studies examining aggression in pediatric and adolescent patients with ASD/ADHD should aim to accumulate evidence for the use of psychotropic medications, which could help clinicians make better decisions.

Persistence of impulsivity in pediatric and adolescent patients with obsessive-compulsive disorder.

AIM: Increasing clinical evidence points to impulsivity as a symptom of obsessive-compulsive disorder (OCD). However, little is known about its persistence over time. METHODS: In this study, we evaluated the performance of 12 pediatric patients with OCD on the Stroop color-word task, which assesses impulsivity, and compared this with age- and sex-matched controls. In parallel, we measured changes in hemodynamic responses during the task, using near-infrared spectroscopy. As patients in the OCD group were naïve to treatment, we compared results before and after 3-year medication with serotonin reuptake inhibitors. RESULTS: We report that, compared with controls, the OCD group had significantly poorer performance and less activation in the prefrontal cortex during the Stroop color-word task. Surprisingly, while serotonin-reuptake-inhibitors treatment reduced OCD symptomology, it did not improve the diminished hemodynamic responses or task performance of these patients. CONCLUSION: Our findings suggest that a persistent deficit exists in the inhibitory control of pediatric patients with OCD; they also provide insight into the pathophysiology of OCD.

Event-Related Potentials Correlate with the Severity of Child and Adolescent Patients with Attention Deficit/Hyperactivity Disorder.

BACKGROUND: Attention deficit/hyperactivity disorder (ADHD) symptoms can continue through adolescence and adulthood, including difficulty in staying focused, paying attention, and controlling behavior, as well as hyperactivity. While children and adolescents with ADHD have functional impairments at multiple dimensions, there are no objective biological indicators to assess the severity of ADHD. Event-related potentials (ERPs) are widely used as a noninvasive method for evaluating sensory and cognitive processes involved in attention tasks. Previous studies have shown that P300 amplitude or latency, a main component in ERPs, is altered in patients with ADHD. However, little is known about the relationship between P300 and the severity of ADHD symptoms. METHOD: We sought to measure both P300 amplitude and latency in ERPs during auditory oddball tasks in 44 patients with ADHD (mean age ± SD 10.28 ± 3.43 years) and 15 age- and gender-matched normally developing children (11.40 ± 3.02 years). In ADHD patients, we also assessed symptom severity using the ADHD rating scale-IV-Japanese version. RESULT: In ADHD groups, P300 amplitude and latency were attenuated and prolonged compared to controls at the frontocentral, centroparietal, and parietal positions. Furthermore, levels of P300 latency at these positions are positively correlated with the inattention subscale scores measured by the ADHD rating scale-IV-Japanese version. CONCLUSIONS: The present study revealed that the degree of P300 latency might reflect the severity of ADHD symptoms with children and adolescents, suggesting that ERPs are a useful technique to evaluate the severity of ADHD symptoms.

Prefrontal dysfunction in pediatric Tourette's disorder as measured by near-infrared spectroscopy.

BACKGROUND: Tourette's disorder (TD) is a chronic childhood-onset disorder characterized by the presence of multiple motor and vocal tics. Despite strong evidence that the pathophysiology of TD involves structural and functional disturbances of the basal ganglia and cortical frontal areas, in vivo imaging studies have produced conflicting results. Recent developments in near-infrared spectroscopy (NIRS) technology have enabled noninvasive assessment of brain function in people with psychiatric disorders. METHODS: We asked 10 individuals with pediatric TD and 10 healthy controls who were age- and sex- matched to perform the Stroop color-word task during NIRS. We used prefrontal probes and a 24-channel NIRS machine to measure the relative concentrations of oxyhemoglobin (oxy-Hb) every 0.1 s during the task. RESULTS: We found that oxy-Hb changes in the prefrontal cortex were significantly smaller in the TD group compared with the control group, especially in the left dorsolateral prefrontal cortex. CONCLUSIONS: Our data suggest that individuals with pediatric TD have a reduced prefrontal hemodynamic response as measured by NIRS.

Increased prefrontal hemodynamic change after atomoxetine administration in pediatric attention-deficit/hyperactivity disorder as measured by near-infrared spectroscopy.

AIM: Atomoxetine, approved in Japan for the treatment of pediatric attention-deficit/hyperactivity disorder (ADHD) in April 2009, is a nonstimulant that is thought to act presynaptically via the inhibition of norepinephrine reuptake. Near-infrared spectroscopy is a non-invasive optical tool that can be used to study oxygenation and hemodynamic changes in the cerebral cortex. The present study examined the effects of a clinical dose of atomoxetine on changes in prefrontal hemodynamic activity in children with ADHD, as measured by near-infrared spectroscopy using the Stroop Color-Word Task. METHODS: Ten children with ADHD participated in the present study. We used 24-channel near-infrared spectroscopy to measure the relative concentrations of oxyhemoglobin in the frontal lobes of participants in the drug-naïve condition and those who had received atomoxetine for 8 weeks. Measurements were conducted every 0.1 s during the Stroop Color-Word Task. We used the ADHD Rating Scale-IV-Japanese version (Home Version) to evaluate ADHD symptoms. RESULTS: We found a significant decrease in ADHD Rating Scale-IV-Japanese version scores, from 30.7 to 22.6 (P=0.003). During the Stroop Color-Word Task, we found significantly higher levels of oxyhemoglobin changes in the prefrontal cortex of participants in the atomoxetine condition compared with those in the drug-naïve condition. CONCLUSIONS: This increase in oxyhemoglobin changes might indicate an intensified prefrontal hemodynamic response induced by atomoxetine. Near-infrared spectroscopy is a sensitive tool for measuring the pharmacological effects of atomoxetine in children with ADHD.

Paliperidone extended release for the treatment of pediatric and adolescent patients with Tourette's disorder.

OBJECTIVE: A subgroup of patients with Tourette's disorder (TD) has symptoms refractory to haloperidol, a standard therapeutic drug for TD. METHODS: We report on three cases of pediatric and adolescent patients who were treated with paliperidone extended release. RESULTS: In two cases, TD symptoms were remarkably improved by switching from haloperidol to paliperidone extended release, and in another case, paliperidone extended release showed significant efficacy in treating TD symptoms as the first-line drug. In all cases, no significant adverse side effects were detected. CONCLUSION: Paliperidone extended release may be a strong candidate for the treatment of pediatric and adolescent patients with TD.

Levetiracetam improves disinhibitory behavior in nonconvulsive status epilepticus.

BACKGROUND: Nonconvulsive status epilepticus (NCSE) is a severe medical condition and heterogeneous disorder defined by different seizure types and diverse etiologies. NCSE occurs commonly in the elderly and is potentially misdiagnosed as a psychiatric disorder. Current treatment options for NCSE are still unsatisfactory. CASE PRESENTATION: We report a case of NCSE in a 55-year-old epileptic male patient with a history of infectious encephalitis, disinhibitory behavior, and a suspected diagnosis of frontotemporal dementia. Add-on levetiracetam (LEV) to carbamazepine treatment improved clinical manifestations and abnormal electroencephalographic discharge. CONCLUSION: With disinhibitory behavior in the elderly, the possibility of NCSE should be considered. Moreover, LEV may be an effective and well-tolerated pharmacotherapy for elderly NCSE patients.

Reduced prefrontal hemodynamic response in pediatric obsessive-compulsive disorder as measured by near-infrared spectroscopy.

Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders. Functional neuroimaging studies of patients with obsessive-compulsive disorder (OCD) have suggested that the frontal cortex and subcortical structures may play a role in the pathophysiology of the disorder. Twelve treatment-naïve children with OCD and 12 age- and sex-matched healthy control subjects participated in the present study after giving consent. The relative concentrations of oxyhemoglobin (oxy-Hb) were measured with prefrontal probes every 0.1 s during the Stroop color-word task, using 24-channel NIRS machines. During the Stroop color-word task, the oxy-Hb changes in the OCD group were significantly smaller than those in the control group in the prefrontal cortex, especially in the frontopolar cortex. The present study suggests that children with OCD have reduced prefrontal hemodynamic response as measured by NIRS.

Comparison of pervasive developmental disorder and schizophrenia by the Japanese version of the National Adult Reading Test.

OBJECTIVE: In adults, it is sometimes difficult to discriminate between pervasive developmental disorder (PDD) and schizophrenia (SCH) when positive symptoms are not outstanding. We examined whether the Japanese version of the National Adult Reading Test (JART), is a valid scale for evaluating pre-morbid intelligence quotient (IQ) in patients with SCH, and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) are useful for helping to discriminate between PDD and SCH. METHODS: Sixteen patients with adult PDD and 16 age-, education- and sex-matched patients with SCH participated in the present study. In addition, two groups were matched for JART and GAF scores. All subjects were scored on the JART and WAIS-R after informed consent on the aim of this study. Examiners who were blind to the diagnoses measured JART and WAIS-R. RESULTS: Significant diagnosis-by-IQ examination interactions were found (F[1,30] = 10.049, P = 0.003). Furthermore, WAIS-R scores of the PDD group were higher than those of the SCH group (P = 0.002) considering two groups were matched for JART. CONCLUSIONS: The comparison of IQ in the PDD group and in the SCH group by JART and WAIS-R might be an easy and useful method for helping to discriminate between PDD and SCH.

Exploration of electroencephalogram response to MPH treatment in ADHD patients.

Attention-deficit/hyperactivity disorder (ADHD) is known to be associated with several diagnostic resting-state electroencephalography (EEG) patterns, including the theta/beta ratio, but no objective predictive markers for each medication. In this study, we explored EEG markers with which the therapeutic efficacy of medications could be estimated at the 1st clinical visit. Thirty-two ADHD patients and thirty-one healthy subjects participated in this study. EEG was recorded during eyes-closed resting conditions, and ADHD symptoms were scored before and after the therapeutic intervention (8 ± 2 weeks). Although comparing EEG patterns between ADHD patients and healthy subjects showed significant differences, EEG dynamics, e.g., theta/beta ratio, in ADHD patients before and after MPH treatment were not significantly different despite improvements in ADHD symptoms. We demonstrated that MPH good responders and poor responders, defined by the efficacy of MPH, had significantly different theta band power in right temporal areas, alpha in left occipital and frontal areas, and beta in left frontal areas. Moreover, we showed that MPH good responders had significant improvements toward normalization in several coherence measures after MPH treatment. Our study implies the possibility of these EEG indices as predictive markers for ADHD therapeutic efficacy.

[Value of ancillary testing in the diagnosis of pervasive developmental disorder in adults].

Recently, there has been increasing interest in adults with pervasive developmental disorder (PDD) who seek general psychiatric services for various psychiatric problems. The diagnosis of PDD requires the careful collection of information about the patient's developmental history. A structured diagnostic interview is useful and should be performed, but has limitations now. The clinical value of the measurement of the Wechsler Adult Intelligence Scale, the Autism-Spectrum Quotient Japanese Version, and the Pervasive Developmental Disorders Autism Society Japan Rating Scale was demonstrated by a questionnaire survey that the authors conducted in 2010. These additional tests are useful if interpreted with caution. For example, a discrepancy between the performance intelligence quotient (IQ) and the verbal IQ in the Wechsler Adult Intelligence Scale does not by itself diagnose PDD. We examined whether the Japanese version of the National Adult Reading Test (Japanese Adult Reading Test; JART), a valid scale for evaluating pre-morbid IQ in patients with schizophrenia, and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) are useful for discriminating between PDD and schizophrenia. Sixteen patients with adult PDD and 16 patients with schizophrenia matched for age, education and sex participated in this study. In addition, the two groups were matched for JART and the Global Assessment of Functioning scores. All subjects were scored on the JART and WAIS-R after giving informed consent for the study. The result was that significant diagnosis-by-IQ examination interactions were found (F [1, 30]=10.049, P=0.003). Also, the WAIS-R scores of the PDD group were higher than those of the schizophrenia group (P=0.002) when the two groups were matched for JART. In conclusion, the comparison of IQ in the PDD group and in the schizophrenia group by JART and WAIS-R might be an easy and useful method for helping to discriminate between PDD and schizophrenia. In addition, the difference in IQ scores measured by JART and by WAIS-R may be helpful in diagnosing PDD. The diagnosis of PDD in adults may be assisted by the use of these additional tests.

Evaluating Guanfacine Hydrochloride in the Treatment of Attention Deficit Hyperactivity Disorder (ADHD) in Adult Patients: Design, Development and Place in Therapy.

Attention-deficit/hyperactivity disorder (ADHD) is characterized by age-inappropriate and impairing levels of inattention, hyperactivity, or impulsivity, or a combination of these characteristics. It is estimated to affect around 4% of adults worldwide. In the past few decades, prescriptions for ADHD drugs (psychostimulants and non-psychostimulants) have increased significantly. However, the efficacy and safety of adult ADHD medications remains controversial. Guanfacine extended-release (GXR) is a non-psychostimulant ADHD drug that is a selective α2A-adrenergic receptor agonist, first approved for treatment of adult ADHD in Japan in June 2019. Our aim was to provide an overview of GXR pharmacology and review the studies on efficacy and safety that have been conducted in adults with ADHD. The beneficial actions of guanfacine are thought to be attributed to the strengthening of prefrontal cortical network connections, which regulate attention, emotion, and behavior via the activity at post-synaptic α2A receptors. Current evidence of GXR efficacy and safety suggests that GXR is an effective monotherapy treatment option for adults with ADHD.

Effects of osmotic-release methylphenidate in attention-deficit/hyperactivity disorder as measured by event-related potentials.

AIM: Attention-deficit/hyperactivity disorder (ADHD) is a relatively common central nervous system disorder in school-age children, which may involve a specific disorder in cognition and/or information processing. Event-related potentials (ERP) are commonly used as physiological measures of cognitive function as they are easily measured and non-invasive. Thus, in the present study, we examined the effects of osmotic-release methylphenidate (MPH) (Concerta), a common treatment for childhood attention-deficit/hyperactivity disorder (ADHD), in ADHD children as measured by ERP. METHODS: Ten ADHD children participated after giving consent. Based on the guidelines for evoked potential measurement, mismatch negativity (MMN) and P300 were obtained by auditory odd-ball tasks. We measured both MMN and P300 in the drug-naive condition and after intake of osmotic-release MPH. RESULTS: The MMN amplitudes after intake of osmotic-release MPH were significantly greater than those in the drug-naive situation at Pz and C4. The P300 amplitudes after intake of osmotic-release MPH were significantly greater than those in the drug-naive situation at Cz and Pz. CONCLUSION: MMN and P300 are sensitive tools for measuring the pharmacological effects of osmotic-release MPH in ADHD children.

Prefrontal dysfunction in attention-deficit/hyperactivity disorder as measured by near-infrared spectroscopy.

Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders with measurement of hemoglobin concentrations as cerebral blood volume. Twenty medication-naïve children with attention-deficit/hyperactivity disorder (ADHD) and 20 age- and sex-matched healthy control subjects participated in the present study after giving consent. The relative concentrations of oxyhemoglobin (oxy-Hb) were measured with frontal probes every 0.1 s during the Stroop color-word task, using 24-channel NIRS machines. During the Stroop color-word task, the oxy-Hb changes in the control group were significantly larger than that in the ADHD group in the inferior prefrontal cortex, especially in the inferior lateral prefrontal cortex bilaterally. The Stroop color-word task used with NIRS may be one useful measurement to assess prefrontal brain dysfunction in ADHD children.

Tai Chi exercise versus rehabilitation for the elderly with cerebral vascular disorder: a single-blinded randomized controlled trial.

BACKGROUND: Cerebral vascular disorder (CVD) might result in a quantifiable decrease in quality of life, which is determined not only by the neurological deficits but also by impairment of cognitive functions. There are few studies that report on the cognitive effect of Tai Chi exercise (Tai Chi) on the elderly with CVD. The purpose of the present study was to examine the cognitive effect of Tai Chi on the elderly with CVD using P300 measurement, in addition to the General Health Questionnaire (GHQ) and Pittsburgh Sleep Quality Index (PSQI). METHODS: A total of 34 patients with CVD were recruited from outpatient Akistu-Kounoike Hospital and randomly assigned to receive Tai Chi (n= 17) or rehabilitation (n= 17) in group sessions once a week for 12 weeks. To examine the time courses of each score (P300 amplitude, P300 latency, GHQ score and PSQI score), repeated-measures analysis of variance was carried out with groups and time as factors. RESULTS: For the time courses of P300 amplitudes and latencies, there were no significant effects of interaction between group and time. However, significant time-by-group interactions were found for Sleep Quality (P= 0.006), GHQ total score (P= 0.005), anxiety/insomnia score (P= 0.034), and severe depression score (P= 0.020). CONCLUSIONS: Tai Chi might therefore be considered a useful non-pharmacological approach, along with rehabilitation, for the maintenance of cognitive function in the elderly with CVD and might be a more useful non-pharmacological approach for the improvement of sleep quality and depressive symptoms in the elderly with CVD than rehabilitation.

Influence of Self-Esteem and Psychiatric Diagnosis on Health-Related Quality of Life in Children and Adolescents with School Refusal Behavior.

BACKGROUND: School refusal behavior (SRB), which is the refusal to attend or remain in school, has been associated with emotional, psychological, and other behavioral problems, as well as a lower health-related quality of life (HRQOL). However, the effects of self-esteem and a psychiatric diagnosis in students with SRB on HRQOL are not yet known. Understanding these relationships could help to develop more effective therapeutic interventions. METHODS: A total of 175 young people (aged 8-18 years old) who visited our medical centers and outpatient clinics participated in the study. This comprised the SRB group (n = 70) and an age- and sex-matched control group (n = 105). Information about any psychiatric diagnosis was collected from medical records, HRQOL was measured using the J-KIDSCREEN-52, SRB was assessed using the School Refusal Assessment Scale-Revised for Japanese Attendance at School, self-esteem was measured using the Rosenberg Self-Esteem Scale, children's mental health status was measured using the Strengths and Difficulties Questionnaire, and social support was measured using the Oslo 3-item Social Support Scale. We performed between-group comparisons and multiple regression analysis. RESULTS: The SRB had a significantly lower HRQOL than the control group in several of the KIDSCREEN-52 dimensions. In the SRB group, 35.7% had chronic disease and 35.7% of their parents had health problems and were receiving treatment. The multiple regression analysis revealed that, within the SRB group, a psychiatric diagnosis was associated with a lower HRQOL. However, this was not the case for a diagnosis of autistic spectrum disorder. Self-esteem positively affected HRQOL in six dimensions of the KIDSCREEN-52 within the SRB group. CONCLUSION: Our results could inform the development of support strategies for young people with SRB. Namely, support that enhances self-esteem could be used to increase HRQOL in young people with SRB. Furthermore, the presence of psychiatric disorders should be assessed as early as possible.

Associations of childhood experiences with event-related potentials in adults with autism spectrum disorder.

Childhood maltreatment is defined as experiencing of physical, emotional and sexual abuse and neglect in childhood. Maltreatment in childhood leads to substantial psychosocial problems later in life in the general population. Individuals with autism spectrum disorder (ASD) have a higher risk of experiencing stressful and traumatic events, such as maltreatment, during childhood. Although childhood maltreatment reportedly leads to psychosocial problems in adults with ASD, the biological associations between childhood experiences and brain function in this population remain understudied. Here, we evaluated the relationships between childhood experiences and event-related potential (ERP) components during the auditory odd-ball task in adults with ASD (N = 21) and typically developed (TD) individuals (N = 22). We found that the higher the severity of sexual abuse, the larger the amplitude of P300 at Fz, Cz, C3, and C4 in individuals with ASD. Conversely, the severity of child maltreatment was associated with P300 latency at Cz and C3 in TD individuals. Moreover, full IQ was significantly associated with the MMN amplitude at Fz, Cz, C3, and C4 in TD individuals. These findings provide the first evidence that ERPs could be used to study the impacts childhood experiences on the brain of individuals with ASD and that childhood sexual abuse has salient impacts on brain function in this population.

Delayed prefrontal hemodynamic response associated with suicide risk in autism spectrum disorder.

Adults diagnosed with Autism spectrum disorder (ASD) are at high risk of experiencing suicidality compared with other clinical groups. Recently, near-infrared spectroscopy (NIRS) studies have investigated the association between frontotemporal functional abnormalities and suicidality in patients with mood disorders. However, whether these prefrontal hemodynamic responses are associated with suicide vulnerability in individuals with ASD remains unclear. Here, we used 24-channel NIRS to examine the characteristics of prefrontal hemodynamic responses during a verbal fluency task in 20 adults with ASD and in age-, sex-, and intelligence quotient-matched healthy controls. In addition, we used Spearman's correlation analysis to identify the relationship between the time-course of prefrontal hemodynamic activation and the current suicide risk in patients with ASD. We found no significant differences between the verbal fluency task-induced prefrontal hemodynamic responses in the ASD vs. control group. However, we found a significant positive correlation between the current suicide risk score and the time-course of prefrontal hemodynamic activation in the ASD group. Thus, the 24-channel NIRS system appears to be useful in assessing suicide risk in individuals with ASD.

Reduced prefrontal hemodynamic response in pediatric autism spectrum disorder measured with near-infrared spectroscopy.

BACKGROUND: Functional neuroimaging studies suggest that prefrontal cortex dysfunction is present in people with autism spectrum disorder (ASD). Near-infrared spectroscopy is a noninvasive optical tool for examining oxygenation and hemodynamic changes in the cerebral cortex by measuring changes in oxygenated hemoglobin. METHODS: Twelve drug-naïve male participants, aged 7-15 years and diagnosed with ASD according to DSM-5 criteria, and 12 age- and intelligence quotient (IQ)-matched healthy control males participated in the present study after giving informed consent. Relative concentrations of oxyhemoglobin were measured with frontal probes every 0.1 s during the Stroop color-word task, using 24-channel near-infrared spectroscopy. RESULTS: Oxyhemoglobin changes during the Stroop color-word task in the ASD group were significantly smaller than those in the control group at channels 12 and 13, located over the dorsolateral prefrontal cortex (FDR-corrected P: 0.0021-0.0063). CONCLUSION: The results suggest that male children with ASD have reduced prefrontal hemodynamic responses, measured with near-infrared spectroscopy.