The Changes in Concentration of Cerebral Oxygenated Hemoglobin During Single Event-Related Japanese Shiritori Task in Patients With Major Depression Disorder: Comparison With Healthy Subjects.

Patients with major depressive disorder (MDD) have been reported to show cognitive impairments in attention, cognition control, and motivation. The purpose of this study is to compare and examine the characteristics of frontal and temporal cortical activity in outpatients with MDD during the word production task (Shiritori) using a single event-related Near-Infrared Spectroscopy (NIRS) measurement method that was originally devised. The subjects were 29 MDD patients and 29 age matched healthy controls. In this task, one session consisted of two contrasting conditions (word production task, control condition), and all subjects alternated between these conditions. Each word was visually presented by a monitor for 0.3 s as an activation task and a fixed circle was presented for 12 s. In the activation task, subjects had to immediately generate a noun that starts with the last syllable of the presented word and they were required to say only creatures. From the data obtained at each measurement point during the 20 trials, and averaged waveform during activation task (20 trials) was calculated for each channel. During the word production task, the MDD patients showed significantly smaller activation than the controls in the prefrontal cortex area and inferior parietal area, especially in the left area. In addition, there was a significant negative correlation between Δoxy-Hb at the bilateral temporal lobe area and HAM-D total score in the MDD patients. These findings suggest that a single event-related NIRS measurement during Japanese shiritori tasks may be useful tool for evaluating psychophysiological indices in MDD patients, that relationship between activation and symptom may be of help in predicting functional outcome in patients.

Comparison of changes in oxygenated hemoglobin during the tree-drawing task between patients with schizophrenia and healthy controls.

BACKGROUND: Tree-drawing test is used as a projective psychological test that expresses the abnormal internal experience in patients with schizophrenia (SZ). Despite the widely accepted view that the cognitive function is involved in characteristic tree-drawing in patients with SZ, no study has psychophysiologically examined it. The present study aimed to investigate the involvement of cognitive function during tree-drawing in patients with SZ. For that purpose, we evaluated the brain function in patients with SZ during a tree-drawing task by using near-infrared spectroscopy (NIRS) and compared them with those in healthy controls. PATIENTS AND METHODS: The subjects were 28 healthy controls and 28 patients with SZ. Changes in the oxygenated hemoglobin ([oxy-Hb]) concentration in both the groups during the task of drawing a tree imagined freely (free-drawing task) and the task of copying an illustration of a tree (copying task) were measured by using NIRS. RESULTS: Because of the difference between the task conditions, [oxy-Hb] levels in controls during the free-drawing task were higher than that during the copying task at the bilateral frontal pole regions and left inferior frontal region. Because of the difference between the groups, [oxy-Hb] levels at the left middle frontal region, bilateral inferior frontal regions, bilateral inferior parietal regions, and left superior temporal region during the free-drawing task in patients were lower than that in controls. CONCLUSION: [oxy-Hb] during the tree-drawing task in patients with SZ was lower than that in healthy controls. Our results suggest that brain dysfunction in patients with SZ might be associated with their tree-drawing.

Characteristics of oxygenated hemoglobin concentration change during pleasant and unpleasant image-recall tasks in patients with depression: Comparison with healthy subjects.

AIM: Patients with major depressive disorder (MDD) have been reported to show cognitive impairment in attention, cognition control, and motivation. The prefrontal cortex plays an important role in the pathophysiology of depression. Neurophysiological abnormalities have been examined in MDD patients by several neuroimaging studies. However, the underlying neural mechanism is still unclear. We evaluated brain function during pleasant and unpleasant image-recall tasks using multichannel near-infrared spectroscopy (NIRS) in MDD patients. METHODS: The subjects were 25 MDD patients and 25 age- and sex-matched healthy controls. Patients were classified according to DSM-IV-TR criteria. We measured the oxygenated hemoglobin concentration change (δoxyHb) in the forehead and temporal lobe during image-recall task with pleasant (e.g., puppy) and unpleasant (e.g., snake) images using NIRS. To check whether all subjects understood the task, they were asked to draw pictures of both image tasks after NIRS measurement. RESULTS: The δoxyHb in the healthy group was significantly higher than that in the MDD group in the bilateral frontal region during the unpleasant condition. A significant negative correlation between the Hamilton Rating Scale for Depression score and δoxyHb was observed in the left frontal region during the unpleasant condition. CONCLUSION: We suggest that image-recall tasks related to emotion measured by NIRS might be a visually useful psychophysiological marker to understand the decrease in the frontal lobe function in MDD patients. In particular, we suggest that the decrease in δoxyHb in the left frontal lobe is related to the severity of depression.

Comparison of changes in the oxygenated hemoglobin level during a 'modified rock-paper-scissors task' between healthy subjects and patients with schizophrenia.

AIM: The purpose of this study, using single-event-related near-infrared spectroscopy (NIRS), was to examine the psychophysiological and social function assessment of 30 schizophrenic patients during a modified rock-paper-scissors task. METHODS: We set up a screen in front of the subjects, on which pictures of hand-gestures for rock, paper, and scissors were randomly presented. Subjects were asked to give verbal answers under the conditions of win, lose, and draw, respectively. Using the 44-channel NIRS system, we evaluated the maximum amplitude of oxygenated hemoglobin, latency, and the area based on the arithmetic mean of resulting values after the task between 30 outpatients with schizophrenia and 30 healthy subjects, and analyzed the frontal pole area, dorsolateral prefrontal region, and parietal association area as regions of interest (ROI). RESULTS: In schizophrenic patients, oxygenated hemoglobin changes (Δoxy-Hb) when losing the task showed a significantly lower level of Δoxy-Hb in ROI than controls. In addition, a significant positive correlation was observed between the Global Assessment of Functioning Scale and Δoxy-Hb in ROI, and a significant negative correlation was observed between the Negative Syndrome scale of the Positive and Negative Syndrome Scale and Δoxy-Hb in ROI. CONCLUSION: From these results, we conclude that Δoxy-Hb levels when performing the modified rock-paper-scissors task assessed using NIRS may be a useful psychophysiological marker to evaluate the cognitive and social functions of schizophrenic patients.

Impaired exploratory eye movements in children with Asperger's syndrome.

OBJECTIVE: Previous eye-tracking studies using an eye mark recorder have reported that disturbances in exploratory eye movements in adult schizophrenic patients are associated with social functioning. The current study sought to determine whether exploratory eye-movement disturbances are present in children with Asperger's syndrome (AS) compared with typically developing (TD) children. MATERIALS/PARTICIPANTS: The participants were 23 children with AS and 23 age-matched TD children. We measured exploratory eye movements using an EMR-8B eye mark recorder and an exploratory eye movement-measuring device. METHOD: Eye movements were recorded while participants freely observed a geometric figure (free viewing task), and while they complied with the instructions of an experimenter (repeat-comparison task). We assessed eye fixation points (EFPs) and total eye scanning length (TESL) in all tasks, and measured the responsive search score (RSS) in the repeat-comparison task. RESULTS: In the free viewing task, children with AS exhibited significantly shorter TESL compared with TD children. In the repeat-comparison task, children with AS exhibited significantly lower RSS. Autism Spectrum Screening Questionnaire scores were negatively correlated with both EFP and TESL, but not RSS. CONCLUSION: The current results revealed that children with AS exhibited dysfunction in exploratory eye movements. Thus, assessing exploratory eye movements in a repeat-comparison task may be useful for detecting social impairment among children with AS.

[Characteristics of single event-related cerebral hemodynamics during verbal task in emotionally charged state measured by multi-channel near-infrared spectroscopy (NIRS) in patients with schizophrenia: comparison with healthy subjects].

Neared infrared spectroscopy (NIRS) is one of the recently developed methodologies which can measure cerebral blood volumes to determine the blood hemoglobin (Hb) concentration simultaneously at multiple points with marked time resolution. Monitoring the changes in the Hb concentration yields site-specific readings on blood flow and, thus, on neural activities. The aim of this study was to examine the characteristics of a single event-related oxyhemoglobin concentration [oxy-Hb] changes in patients with schizophrenia using multi-channel NIRS during a word generation task, Japanese 'Shiritori', and single-word generation task in an emotionally charged state induced by three facial expressions of "crying", "neutral", and "smiling" babies' photographs. Thirty-four patients with schizophrenia and 34 age-matched healthy controls participated in the present study after giving consent. In healthy controls, [oxy-Hb] changes when viewing the "crying" baby's photograph were significantly larger than when viewing the "smiling" baby's photograph. On the other hand, in patients with schizophrenia, [oxy-Hb] changes when viewing the "smiling" baby's photograph were significantly larger than when viewing the "crying" baby's photograph. These results suggest that cautions/execution functions in patients with schizophrenia during the single event word "Shiritori" task measured by multi-channel NIRS were impaired. It was also suggested that, in patients with schizophrenia, the affective reaction influenced by each photograph may be different from healthy controls (mismatch). Multi-channel NIRS can be a useful tool for research and clinical purposes in psychiatry.

Left eye scanning deficit in schizophrenia patients under emotional loading task: comparison with healthy controls.

The aim of the present study was to evaluate and characterize visual cognitive function and the effect of emotion in patients with schizophrenia.We recorded exploratory eye movements as biologic markers in 40 schizophrenic patients and 40 age-matched healthy controls. Total eye scanning length (TESL), total number of gaze points (TNGP), and TNGP in right (right TNGP) and left (left TNGP) visual fields on screen were calculated as subjects viewed affectively charged pictures (smiling and crying babies) with fitting sounds.TESL of patients was shorter than that of controls when viewing pictures of smiling babies while recalling pleasurable events, and significantly decreased under negative emotional loading when viewing crying babies while recalling sad events. TESL recovered to the original values after loading positive emotion again in the controls. However, TESL did not recover to the original values in schizophrenic patients. TNGP showed similar alterations in the emotional loading task. When TNGP was evaluated in left and right fields, in patients, the non-recovery of TNGP was only observed in the left side. TESL and left TNGP were negatively correlated with negative symptom scores on PANSS.Schizophrenic patients'eye movements in the left visual field screen during the emotional loading task were different from those of controls, which suggests that visual cognitive function is impaired in the right brain in schizophrenic patients. Exploratory eye movements are a useful marker of visual cognitive function, and are a useful tool to evaluate the influence of emotion in schizophrenic patients.

Changes in task-associated cerebral blood induced by role lettering: measurement by multichannel near-infrared spectroscopy.

Using optical topography (near-infrared spectroscopy: NIRS), relative changes in oxidized hemoglobin (oxy-Hb) were measured before and after the introduction of Role lettering. Tasks performed during measurements included antegrade (from the subject to other persons) and retrograde (from other persons to the subject) mental imaging and writing tasks. All subjects were junior high school students. Relative changes in oxy-Hb were measured before and 3, 6, and 12 months after the start of Role lettering. The region of interest (ROI) was determined based upon the motor cortex region of hand movement and upon relative oxy-Hb changes noted before any Role lettering. For antegrade mental tasks, oxy-Hb increased significantly in right-sided ROI after 3 months; this increase persisted at 1 year. For retrograde mental tasks, oxy-Hb significantly increased bilaterally at 3 months, an effect that also persisted at 1 year. With the antegrade writing task, no significant difference was observed throughout the study; with the retrograde writing task, oxy-Hb level decreased significantly in right lateral ROI after 6 months; the decrease persisted at 1 year. The number of words produced after Role lettering increased significantly in both antegrade and retrograde writing tasks at 1 year, compared with the number before Role lettering. Role lettering thus altered mental activity, particularly in the right hemisphere. Retrograde writing tasks, similar to those employed in the actual practice of Role lettering, reduced right hemispheric function; continuation of the task enhanced performance. Role lettering studies using NIRS may provide useful psychophysiologic indices.

Characteristics of exploratory eye movements in elderly people: possibility of early diagnosis of dementia.

BACKGROUND: Visual cognitive dysfunction is one of the most important signs indicating the early stage of dementia. Thus, visual testing could be used as an aid to the clinical diagnosis of dementia. In the present study, exploratory eye movement was measured to evaluate visual cognitive function in elderly subjects, including those with dementia. METHODS: We analyzed responsive search scores (RSS) from exploratory eye movements of 300 subjects who were examined with an eye mark recorder while viewing S shaped figures. Subjects were divided into three groups (dementia, intermediate, healthy) from the values of the Revised Hasegawa Dementia Scale (HDS-R), the Mini-Mental State Examination (MMSE) and the Clinical Dementia Rating. We further divided the intermediate groups into two subgroups, the high score and low score groups, based on RSS. In 202 subjects, Z-scores of voxel-based specific regional analysis system for Alzheimer's disease (VSRAD) were obtained from magnetic resonance imaging (MRI). RESULTS: RSS of the dementia group were significantly lower than those in the intermediate and healthy groups, in order: dementia < intermediate < healthy groups. RSS of the low score intermediate group was significantly lower than that of the high score intermediate group. There was no significant difference between the low score intermediate and dementia groups, or between the high score intermediate and healthy groups. No significant differences of either HSD-R or MMSE were observed between the low score and the high score intermediate groups. The Z-score of VSRAD using MRI in the low score intermediate group was significantly higher than that in the high score intermediate group. CONCLUSIONS: These findings suggest that RSS using an eye mark recorder is a useful psychophysiological marker to evaluate the early stage of dementia as well as at-risk elderly people.

[Development of human visual cognitive function in childhood: evaluation by exploratory eye movements to a picture of a smiling face].

To evaluate the development of human visual cognitive function in childhood, we examined exploratory eye movements in 78 healthy subjects using affective pictures. We divided them into six groups, each of which comprised 14 subjects (7 boys or men, 7 girls or women) at the indicated ages. Exploratory eye movements were recorded via gazing points using an eye-mark recorder. The total eye scanning length (TESL) of gaze points increased significantly with age, and the mean eye scanning length, in 4-6-year-olds was significantly shorter than in the others groups. The total number of gaze points (TNGP) on the left half of the screen increased significantly with age. The left TNGP in 4-6-year-olds was significantly smaller than in the other groups. The response search score (RSS) measured in 8 areas of the screen increased significantly with age. It was concluded that exploratory eye movements are useful markers to estimate the development of human visual cognitive function in childhood.

Effects of emotionally charged sounds in schizophrenia patients using exploratory eye movements: comparison with healthy subjects.

AIMS: Emotion-associated sounds have been suggested to exert important effects upon human personal relationships. The present study was aimed to characterize the effects of the sounds of crying or laughing on visual cognitive function in schizophrenia patients. METHODS: We recorded exploratory eye movements in 24 schizophrenia patients (mean age, 27.0 +/- 6.1 years; 14 male, 10 female) and age-matched controls. The total eye scanning length (TESL) and total number of gaze points in the left (left TNGP) and right (right TNGP) visual fields of the screen and the number of researching areas (NRA) were determined using eye-mark recording in the presence/absence of emotionally charged sounds. RESULTS: Controls' TESL for smiling pictures was longer than that for crying pictures irrespective of sounds. Patients' TESL for smiling pictures, however, was shorter than for crying pictures irrespective of the sounds. The left TNGP for smiling pictures was lower in patients than controls independent of sound. Importantly, the right TNGP was significantly larger with laughing sounds than in the absence of sound. In controls, the NRA for smiling pictures was significantly greater than for crying pictures irrespective of sound. Patient NRA did not significantly differ between smiling and crying pictures irrespective of sound. CONCLUSION: Eye movements in schizophrenia patients' left field for smiling pictures associated with laughing sounds particularly differed from those in controls, suggesting impaired visual cognitive function associated with positive emotion, also involving pleasure-related sounds, in schizophrenia.

Developmental characteristics of visual cognitive function during childhood according to exploratory eye movements.

To evaluate the development of visual cognitive function in childhood, we examined exploratory eye movements in 84 healthy subjects viewing picture-based stimuli. Age-defined groups included 4- to 6-year-olds, 7-year-olds, 10-year-olds, 14-year-olds, 16-year-olds, and adults. In each group, 7 subjects were male and 7 were female. Exploratory eye movements, recorded as gaze points using an eye-mark recorder, were analyzed in terms of the total number of gaze points (TNGP); total eye-scanning length of gaze points (TESL); total number of gaze points on the left (l TNGP) and right (r TNGP) of the screen; and responsive search score (RSS) on the left (l RSS) and right (r RSS) of the screen. Both the TESL and TNGP increased significantly with age. The TESL and TNGP of 16-year-olds and adults viewing a repeat-comparison figure were significantly greater than when viewing a comparison figure. During the repeat-comparisons, the TNGP in 4- to 6-year-olds was greater on the right than the left; the opposite was true in 16-year-olds and adults. The RSS in 4- to 10-year-olds was greater on the right than the left; 16-year-olds and adults showed the reverse findings. Thus, in the repeat-comparison task, TNGP, TESL, TNGP, and RSS differences between left and right visual fields are useful biologic markers for estimating the development of visual cognitive function.