Some studies have claimed that in face recognition holistic processing that deals with the spatial relation of each component and their global configuration predominates over other types of objects. In order to examine impaired processing of the visual system in prosopagnosia, this study investigated IM, a male with prosopagnosia but without object agnosia. In Experiment 1, we examined whether IM normally shows a face inversion effect in which recognition of inverted faces is impaired more than that of upright faces. His performance was severely impaired in the simultaneous unknown-face matching task. Moreover, IM showed inverted face inversion effect. He performed better at matching inverted faces than upright faces. In Experiment 2, he was asked to identify local or global letters of hierarchical stimuli with local letters hierarchically nested within global letters. In contrast to normal subjects, IM demonstrated “local precedence” in that his reaction time was faster for local than for global letters and his identification score was worse in the large visual angle condition (9°) compared with the small visual angle (3°). These results suggest that holistic processing is impaired in IM and that his prosopagnosic symptom may be caused by dysfunction of such visual processing system.
We investigated visuo-spatial working memory function in eleven frontal lobe-damaged patients (FDP) using a maze task, and compared their performance with that of Parkinson disease patients (PDP) as we reported previously. The number of trials to find the correct route was greater in the FDPs than in the nine normal controls, and their error patterns were different from those of either the normal controls or PDPs. We found two error patterns : one adopting the same incorrect turn repeatedly at the same position in a maze (type 1), and the other a failure to recall the correct route found in the preceding trial (type 2). The difference in error patterns between FDPs and PDPs shows that the ability to reject an inappropriate choice and select the correct one is impaired in the FDP, whereas disability in the PDP is mainly caused by deficient encoding and storage function. Consequently, the results suggest that the frontal lobe may play a major part in the monitoring of changing situations and the manipulation of information, rather than encoding and storage during working memory tasks.
The patient was a 72-year-old, right-handed male. He exhibited apraxia of speech after infarction of the lower part of the left precentral gyrus. The purpose of this research was to quantify articulation errors and change of prosody in apraxia of speech. We examined the relationship between the these disorders, and investigated the basic symptoms. Recovery in this patient was very quick and he left the hospital 18 days after development of the symptoms. Utterance was examined on the 2nd, 4th, 12th and 18th days. Soon after onset we observed distortions, substitutions and repetitions in the errors of articulation. On the first two examinations, the occurrence rate of abnormal prosody was higher than that of errors of articulation. The findings suggested that there is no clear relationship between abnormal prosody and articulation errors, because in both aspects the rate of coincidence was 0-50%. Furthermore, comparison of this patient with a paretic dysarthria group in nonverbal repetitive oral movements demonstrated a significant fall in the patient's speed of movement. Although nonverbal simple continuation oral movements were no problem 18 days after onset, parapraxia was observed in complicated repetitive oral movements. Therefore, the nonverbal repetitive oral movements of this patient suggested that coordination of the articulatory organs is impaired in tandem with complications in movement patterns.
There have been few reports on patients with dementia using electronic devices to assist them in following daily schedules. This study attempted to evaluate the use of an IC Recorder and ChatBox for voice output to a patient with Alzheimer's disease. Messages were recorded by a speech therapist and played to prompt the patient's daily activities, including reminders not to leave the house to take the dog for a walk. The patient did well in initiating actions in response to the spoken messages. His most troublesome behavior, leaving the house, ceased completely. This study suggests that electronic devices may have potential as memory aids for some patients with dementia.
We studied an effect of alcoholic olfactory stimulation on cerebral lateralization in the cognition of non-verbal sounds on 26 adults (10 males and 16 females, 20-30 years old) , using dichotic listening test. This consisted of a set of pure, warble tones and complex sounds. The results indicated that the males have a significant right cerebral (left auditory) predominance in the lateralization for cognition of non-verbal sounds (p < 0.05) , and that the females have a tendency to right cerebral predominance but without statistical significance. However, after the alcoholic olfactory stimulation, both the males and females developed a significant left cerebral (right auditory) predominance (p < 0.05). In the present experiment, an alcoholic olfactory stimulation presented an obvious shift from the right to left cerebral predominance for cognition of the non-verbal sound tasks in both sexes. The fact suggested a possibility that an olfactory stimulation probably affecting emotion also could influence cerebral lateralization in non-verbal sounds cognition.
Conduction aphasia is a subtype of aphasia whose core disturbances are in the processing of phonological mapping. We have observed eight cases of conduction aphasia during the past 10 years. Five subjects were right-handed and the rest were not right-handed. Six subjects had been affected in the left hemisphere, and the rest in the right hemisphere. We studied their lesions by MRI, CT and/or SPECT, and evaluated the neuropsychological symptoms in each subject. The results were as follows. (1)The five right-handed subjects who had damage in the left hemisphere exhibited a common lesion in the supra marginal gyrus, suggesting that in humans with “normal” cerebral lateralization the center for phonological mapping is in the supra marginal gyrus. (2)Results for the three non-right-handed subjects thought to have “anomalous” cerebral lateralization suggested that among the subcomponents of language processing, the phonological mapping system is able to localize independently in either hemisphere. (3)All subjects showed buccofacial apraxia, suggesting that phonological mapping and buccofacial praxis have some compatibility in terms of localization in the brain.
The present study quantitatively examined the accuracy of phonemic identification in aphasic patients. Eight aphasic patients with left-hemisphere lesion and 15 normal subjects participated in the study. The speech sounds chosen for the investigation were monosyllables varying by manner of articulation (stops vs. glides). The /ba/-/wa/ continuum consisted of 10 synthesized stimuli varied by transition duration of the first and second formants (F1 and F2) . The accuracy of /ba/-/wa/ identification was assessed in terms of formant transition duration in the subjects' right ear. The following results were obtained. (1)The accuracy of /ba/-/wa/ identification in the right ear of aphasic patients was significantly poorer than that of normal subjects ; that is, phonemic identification performance was deteriorated in many aphasic patients. (2)The /ba/-/wa/ identification performance (normal/borderline/abnormal) moderately correlated with auditory resolution performance in the right ear of the aphasic patients as measured using the click fusion threshold test (normal/borderline/abnormal). However, the correlation between /ba/-/wa/ identification accuracy and the click fusion threshold was below a significant level. We concluded that (1)the degraded identification function in the right ear of aphasic patients may be partly attributable to disturbance of auditory resolution, and (2)also partly attributable to inability to assign reliable category labels to speech stimuli based the memory of phonemes.
Four patients with dementia of Alzheimer type (DAT) were introduced to rehabilitation of memory based on their problems in daily living, such as names of rehabilitation staff, places where they live, dates, schedules and routines. After 4 months, few patients revealed any improvement on the Mini Mental State Examination, Hasegawa Dementia Scale-Revised, Wechsler Memory Scale-Revised, or Rivermead Behavioral Memory Test. With respect to rate of correct answers for tasks based on problems in daily living, all patients revealed improvement in names and places, but no patients improved concerning dates, schedules or routines. These results indicate that tasks relating to names and places that involve stationary and semantic factors should be introduced. Tasks of remembering dates, schedules and routines that involve unstable and episodic factors did not seem to improve. These findings suggest that it is important to support the daily living of DAT patients with pragmatical adjustments and services. It is also important to consider their emotional conditions.