Research on cognitive dysfunction has two aspects : a clinical aspect to understand symptoms and attribute them to diagnosis and treatment, and a neuroscientific aspect to clarify the neural mechanisms involved in cognitive functions through an in-depth understanding of symptoms. In recent years, many fields, including psychology, gerontology, informatics, sociology et al., have become involved in research related to cognitive dysfunction. Furthermore, in order to provide appropriate support for patients with cognitive dysfunction, it is important for researchers to connect with government, welfare, and local communities, and to fully incorporate the opinions of patients and caregivers into policies. Therefore, individuals involved in research on cognitive dysfunction need to connect with people in a broader range of fields than before, and to cooperate mutually in conducting research while utilizing their fields of expertise. To accomplish this, it is considered necessary to provide information that is easily comprehensible to individuals from diverse fields and to cultivate interest in different fields.

  In stroke rehabilitation, the emphasis is often placed on motor impairments and dysphagia. However, stroke is the most common cause of higher brain dysfunction, and understanding the characteristics of higher brain dysfunction and determining how to address it in stroke treatment is essential. Higher brain function is integral to all daily activities, and interventions should be approached from both the motor and cognitive perspectives to enhance independence in daily living. In addition to functional impairments such as aphasia, apraxia, agnosia, attention impairment, memory impairment, and emotional disturbance, individuals with higher brain dysfunction invariably experience some form of daily life impairment. It is crucial to continuously assess and analyze the specific daily life challenges observed and evaluated for each patientʼs condition, selecting treatment techniques that can address these issues. Monitoring the effects of treatment while consistently contemplating the recovery mechanism remains pivotal.

  Objective assessment of the neuronal abnormalities in cases of traumatic brain injury (TBI) with diffuse axonal injury (DAI) is crucial to understanding the underlying pathology, as well as from the point of view of facilitating socioeconomic support for these patients. Neuronal integrity can be evaluated by benzodiazepine binding using ¹²³I-iomazenil (IMZ) SPECT. We aimed to investigate the extent of neuronal damage in cases of TBI with DAI using ¹²³I-IMZ SPECT and MRI. The findings in 31 patients with TBI without any major focal brain lesions were compared with those of 25 age-matched normal controls. Subjects underwent ¹²³I-IMZ SPECT and MRI, and also assessment by cognitive function tests. The partial volume effect of ¹²³I-IMZ SPECT was corrected using MRI. Regional benzodiazepine binding and brain atrophy in TBI were assessed based on the volume of interest and voxel-based analysis. In the patients with TBI, decreased binding of ¹²³I-IMZ was detected in the medial frontal/orbitofrontal cortex, posterior cingulate gyrus, cuneus, precuneus, and superior region of the cerebellum. The decreased ¹²³I-IMZ binding in the cuneus and precuneus was associated with cognitive decline after the injury. In the patients with TBI, brain atrophy was detected in the frontal lobe, anterior temporal and parietal cortex, corpus callosum, and posterior part of the cerebellum. ROC analysis of ¹²³I-IMZ SPECT for the detection of neuronal injury showed a high diagnostic ability of ¹²³I-IMZ binding for TBI in the cingulate gyrus, medial regions of the frontal, parietal, and occipital lobes, and superior region of the cerebellum. Evaluation of the neuronal integrity by ¹²³I-IMZ SPECT provides important information for the diagnosis and pathological interpretation in cases of TBI with DAI.

  Traumatic brain injury is classified into two major categories. One is focal brain injury caused by direct force and the other is diffuse axonal injury which is caused by rotational force. There are many patients who suffered from mixed type of those two injury types. Orbitofrontal cortex is found to be injured in more than half of the patients with focal injury and leads to those symptoms which are related to this lesion. On the other hand, brain volume reduction is found in corpus callosum and other deep white matter structures, thalamus and other deep grey matter structures, cerebellum, and brain stem in the patients with diffuse axonal injury. Therefore, the symptoms of this type of brain injury correspond to these brain regions. However, there are many symptoms in which underpinning neural system has not been found up to now. In this article, I classified the symptoms of traumatic brain injury into those with and without known etiology and made some explanation.

  The aim of this study was to investigate the characteristics of naming deficits in patients with aphasia (PWA) , focusing on response time and related factors. Additionally, the study explored whether the naming performance in PWA could be improved by delaying the onset of naming. The subjects were 19 PWA. The method involved a line drawing naming task, and response times for correct and error responses were measured. Based on this, the time range in which the cumulative relative frequency of error response times reached 80% was extracted for each PWA and defined as the error response time. (Error Response Time : 80%ERT) . Subsequently, different naming tasks with varied naming response times (80%ERT condition and immediate condition) were implemented. In the 80%ERT condition, PWA were prompted to name the stimulus when 80%ERT had elapsed since stimulus presentation. The results revealed that PWA exhibited longer response times for error responses compared to correct responses, with significant individual differences. Furthermore, it was observed that cases with better SLTA (Standard Language Test of Aphasia) naming performance tended to show improvement in naming performance through delayed initiation. In conclusion, the study discussed the clinical significance of considering naming initiation time in PWA naming training.