[in Japanese]

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The neural mechanisms supporting the recovery from the aphasia have long been discussed. Wide spectrum of brain areas including non-dominant hemisphere are thought to participate in this process in various fashions. [METHOD] We measured brain activities by near infrared optical topography (OT) during word generation test in 17 cases who are in their recovery phase from post-stroke aphasia. OT uses near infrared light reflected from the brain tissue carrying the information of regional brain blood volume change. Largest advantage of OT over the other brain mapping methods is its portability and tolerance for head movements. Therefore, OT is suitable for the measurement of pathological cases who are not constantly and perfectly collaborative during the examinations. [RESULTS] Three patterns were observed. 1 : nearly normal activations in dominant hemisphere, 2 : abnormal (inverted) activities in dominant hemisphere, 3 : activities in non-dominant hemisphere. These patters were observed in similar frequencies. In 7 cases, activities in non-dominant side were observed. Among them, four cases were followed up by OT showing the activities shifted toward dominant side within several months. [CONCLUSION] Our observations suggest that the method of speech therapy should also dynamically change according to the on-course pattern of brain activities. As OT is more suitable for brain mapping in clinical situations than fMRI, it may offer practical methodology in deciding the selection of various speech therapies.

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We examined the effects of item similarity on picture naming among aphasic patients. The subjects were seven aphasic patients. They were presented pictures and requested to name them. The items were selected according to phonological and semantic similarities. The first list consisted of randomly selected words, the second of same-category words, and the third of words with the same initial phonemes. Correct response rates and error incidence were compared among the three lists. Correct rates and incidence of perserveration for the lists of semantically and phonologically related words were higher than those for the list of non-related words. The incidence of semantic paraphasias with the list of semantically related words was higher than that with the list of non-related words. The incidence of paraphasias without semantic relations to target words was lower than that for the list of non-related words. The incidence of circumlocutions in the list of phonologically related words was higher than that in the list of randomly selected words. The incidences of phonemic paraphasias, paraphasias without phonological relations, and neologisms for the list of phonologically related words were lower than those for the list of randomly selected words. These findings suggested that the responses on picture naming were influenced by item similarity.

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The ability to recognize facial expressions of emotions has been argued to play an important role in social communication. Recently, there has been a growing interest in the investigation of age-related changes in the ability for facial expression recognition. A majority of the aging-related studies on facial expression recognition utilized photographs of prototypical facial expressions of basic emotions as test stimuli, reporting differential age-related changes in the ability to recognize different emotions. However, the difficulty levels for the recognition of these prototypical facial expressions differ substantially across different emotions. Consequently, the differential agerelated changes observed in earlier studies may have been confounded by such differential difficulty levels. Therefore, this study utilized a novel test for facial expression recognition, in which the difficulty levels were fully controlled by means of morphing and item response theory. This test aims to provide an unbiased description of age-related changes in facial expression recognition. A comparison of the test scores of the old and young participants with regard to facial expression recognition revealed an age-related improvement in the recognition of happiness and an age-related deterioration in the recognition of other basic emotions, in particular, anger, among the old participants. These results indicated the possibility of age-related variation in the capacity for recognizing facial expressions that vary between happiness and other basic emotions. The mechanisms underlying the differential age-related changes are discussed in terms of neurological and socio-developmental perspectives.

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The performance of pursuant loss-resulting paper-rock-scissors with the hands is known to require control and integration of frontal lobe function. However, what area of the brain is actually activated during pursuant paper-rock-scissors remains unclear. Here, we evaluated how the brain functions during loss-resulting or tie-resulting pursuant paper-rock-scissors with the dominant or non-dominant hands, using a 3-tesla functional MRI in normal right-handed subjects. Data analysis was carried out using Brain Voyager^TM software (version 4.9.1), and the differences between the resting and movement conditions were statistically evaluated using a general linear model (single study), convolved with the synthetic canonical hemodynamic response function as supplied by Brain Voyager. Significance was reported at a corrected p<0.05 level (F values, 5.2) by the multiple comparison method (Bonferroni's correction). For group data analysis, all the individual data sets were averaged in Talairach space. The results showed that activated blood oxygenation level-dependent signals were observed in the frontal lobe, supplementary motor area (SMA), sensorimotor area, and cerebellar hemisphere when a pursuant paper-rock-scissors task was performed. Interestingly, the right SMA was activated more strongly during tie-resulting pursuant paper-rock-scissors with the left hand, while the left SMA was activated more strongly during loss-resulting pursuant paper-rock-scissors with the left hand. In conclusion, these findings suggest that the left SMA might be associated with inhibition of stereotypical performance and monitoring of conflict in the subject's mind. Further investigation is required to clarify more detailed functions of the left SMA.

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The PQRST method of studying is widely promoted in Western nations. This strategy consists of five steps : Preview, Question, Read, Self-Recitation and Test, which revealed relative effectiveness compared to the other strategies. Now we are going to report on a successful case of PQRST training for a duration of 2 months, with a patient who had memory problems seven and a half months after his brain injury. Usually PQRST approach uses verbal cues, but we also used visual cues because his visual memory was relatively intact. In this case, it was hypothesized that the PQRST approach would stimulate his retention ability would improve. We also examined an erroeless learning approach which Baddeley had disclosed the efficacy of, and this we confirmed. The patient showed a slight degree of perseveration only when studying, it is all the more certain that studying is an effective means of treatment. After treatment his test score improved significantly. He gained progressive performance on episodic memory and daily living activities, and finally he returned to his employment.

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Corticobasal degeneration (CBD), once considered a pure motor disorder, is now regarded also as a cognitive and behavioral disease. The purpose of the present article is to discuss the association between the dominant side of motor symptoms and frontal/cognitive impairments, an issue that to date has not been fully clarified.
We studied, during the average period of 3.3 ± 2.0 years, the frequency and temporal order of frontal/cognitive symptoms in association with the dominant side of motor impairment in 14 patients who satisfied the diagnostic criteria of CBD. Motor symptoms were more frequent on the right side (right 11, left 3).
Frequent frontal symptoms included alien hand signs, psychomotor slowness, abulia, indifference, emotional disturbance, disinhibition and frontal release signs. Frontal signs were more prevalent in patients with left-dominant motor symptoms and tended to appear somewhat later in the clinical course.
In contrast, cognitive impairments were more common in patients with right-dominant motor symptoms in the earlier clinical stages, but the difference in prevalence between the groups disappeared within five years after onset. Common impairments included dysarthria, word-finding difficulty, taciturnity, agraphia and apraxia. Speech and writing difficulties were of earlier onset and appeared to be the presenting symptoms in some patients with right-but not left-dominant motor impairments. Apraxia was characterized as a mixture of ideomotor and limb-kinetic apraxia that appeared more common in patients with right-dominant motor symptoms and tended to appear after the first two years.
In sum, expressive speech and writing disturbances may be the initial presenting symptoms in patients with right-sided motor symptoms while frontal signs may be of a later presentation and more prevalent in those with left-sided motor symptoms.

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