Alleys in visual space

Geometry of frameless visual space is dealt with. First, parallel and equidistant alleys, horopters in the horizontal plane of eyes' level are discussed within the framework of the Luneburg's model that the frameless visual space is a Riemannian space of constant curvature. That basic postulate and the specific mapping functions assumed by Luneburg between the euclidean map of visual space and the physical space are kept separate, and efforts are directed to make the model applicable to more natural conditions of our visual space. A possibility is pointed out to remove the constraint “frameless” in the sense that perceptual geometrical properties are primarily determined by the convergence of optic axes. So far, only alleys in the horizontal plane extending from us toward infinity have been studied, but more often we perceive parallel lines, horizontal or vertical, in front of us like shelves of a bookcase. Hence, equations are derived for horopter plane appearing fronto-parallel in the three-dimensional visual space and alleys running horizontally or vertically on the horopter plane. It is shown that parallel and equidistant alleys are not the same in the horopter plane as in the horizontal plane, if the visual space is not euclidean. A method to evaluate the discrepancy between the two alleys without using any mapping functions is stated with some numerical examples.     

Testing for developmental continuity or discontinuity: Class inclusion and reversal shifts

Often the data in cognitive development consist of continuous cross-sectional increases in the proportion of children who respond in one of two ways to a diagnostic task. Such developmental trends are, however, ambiguous with reference to the course of individual, longitudinal development because they could be the result of either saltatory or gradual ontogenetic change. The present research tested a nonlongitudinal procedure for discriminating between these two alternatives. This procedure involves the administration of several equivalent versions of the diagnostic task at weekly intervals to children within a given age level in order to obtain a frequency distribution of the number of “successes” produced by each child. A bimodal distribution is interpreted as indicating saltatory ontogenetic change, while a unimodal distribution is taken to indicate gradual change. This method was applied to Piaget's class-inclusion problem and to the optional-shift task by administering four versions of each task to a range of different age-level samples. The optional-shift task produced clearly unimodal, bell-shaped distributions at all tested age levels, results which were interpreted to indicate a gradual ontogenetic increase in the probability of making reversal shifts. On the other hand, the frequency distributions for the class-inclusion task, at the appropriate age levels, were distinctly bimodal, and therefore consistent with a discontinuous ontogenetic transition. The capacity of the repeated-measures method to produce reliable within-task results and to differentiate between tasks was thus demonstrated.     

Velar movements during speech in a patient with apraxia of speech.

A fiberscopic observation of velar movements during speech was made of a patient diagnosed as having apraxia of speech. Repeated utterances of the same word showed a marked variability in terms of the pattern of velar movements accompanied at times by a phonetic change. In spite of such a variability, the general successional pattern of velar gestures for a given phonetic context approximated the normal pattern. During the production of nasal and nonnasal consonants the velum tended to take “neutral” positions. Anticipatory coarticulation was present, but some deviation from normal patterns was occasionally observed. Based on these observations, possible mechanisms responsible for the syndrome called apraxia of speech were discussed.     

The recovery processes of two English-Japanese bilingual aphasics

The recovery processes of two English-Japanese bilingual aphasics, one with Broca's aphasia and the other with Wernicke's aphasia, were investigated with special emphasis on the effect of language therapy. The degree of impairment initially manifested in English and Japanese was almost equivalent in each case, the pattern of impairment corresponding to the respective types of aphasia. In both cases, systematic, controlled language therapy was conducted. Analysis of the recovery courses revealed that language therapy was one decisive variable in the relative degree of recovery of a bilingual aphasic's two languages. The type of aphasia appeared to exert a crucial influence on the relative recovery rate of different modalities.     

Abnormal articulatory dynamics in a patient with apraxia of speech: X-ray microbeam observation

The temporal organization of articulatory movements in a patient diagnosed as having apraxia of speech was explored by means of pellet tracking techniques using an X-ray microbeam system. The results indicated that the temporal organization among different articulators of the patient was sometimes disturbed in his production of a meaningful Japanese word /deenee/. It was also observed that the pattern and velocity of the articulatory movements of the patient in repetitions of monosyllables were different from those of typical dysarthric patients.     

Geographical profiling incorporating neighbourhood-level factors using spatial interaction modelling

The aim of this study was to examine the applicability of methods that use spatial interaction modelling to predict the most probable area for an offender's residence. Tokyo, which is the capital of Japan and is divided into 1507 square-kilometre zones, was selected as the study area. We analysed 4316 criminal trips to commit residential burglaries by 1089 offenders who lived in Tokyo. The following neighbourhood-level factors, and a distance-decay effect between zones, were incorporated into the proposed model: the size of the residential population aged 15–59 years in origin zones, the numbers of households living in detached houses, newcomers, the number of police facilities in destination zones, and the spatial structures of the criminal trips. Search areas calculated by the proposed model were smaller than previous models, suggesting that neighbourhood-level factors are important for predicting the location of an offender's residence.     

Aphasic's comprehension of sentences expressing temporal order of events

Fifty-seven aphasic patients' comprehension of five sentence forms which express the temporal order of events has been investigated. Three major patterns of errors of temporal relations have emerged. The dominant pattern is exhibited by patients making errors on Before's but not on After's. The second and third patterns comprise a fewer number of patients making errors on After's but not on Before's and those making errors on both Before's and After's, respectively. It has been shown that different syndromes of aphasia are equally distributed among these three patterns. In the follow-up study of several patients, fluctuating courses of recovery in which comprehension of before and after alternately increases and decreases have been observed. These results are discussed in connection with a possible account of the acquisition of before and after in Japanese.     

Voice onset time characteristics in apraxia of speech

In order to examine the timing control of laryngeal and supralaryngeal articulatory adjustments in apraxia of speech, voice onset time (VOT) data for stop consonants in monosyllables /de/, /te/, /ge/ and /ke/ were obtained from four apraxic subjects and compared with those of fluent aphasic and normal (both young and aged) speakers (Experiment 1). The results indicated that the VOT distribution patterns of the apraxic patients differed markedly from those of the other speakers. A second experiment was conducted to determine whether the VOT distribution patterns of these four apraxic patients and of two normal controls would change with a lapse of time (Experiment 2). The results of the second experiment demonstrated marked changes in the VOT distribution patterns over time in half of the apraxic patients examined, but essentially no change in the normal controls.     

The effect of semantic plausibility on sentence comprehension in aphasia

Tested were 50 aphasic patients (16 Broca's, 15 Wernicke's, 10 global, and 9 amnesic), 13 nonaphasic brain damaged patients, and 13 normal adults to evaluate the effect of semantic plausibility on sentence comprehension in active affirmative declarative sentences with a sentence-picture matching task. A plate of two pictures was provided for each stimulus sentence, and the subject was required to choose the picture corresponding to the sentence presented auditorily. Two types of sentences in terms of plausibility were prepared, i.e., probable sentences (P) describing common events in our daily life and improbable sentences (I) describing rare events. There were four kinds of combinations of a picture with the other to make a correct/(distractor) set, i.e., P/(P), P/(I), I/(P), and I/(I) constructions. The results indicated that probable sentences were more comprehensible than improbable sentences, and that the effect of semantic plausibility did not differ among aphasic types.     

Velar movements during speech in two Wernicke aphasic patients

The articulatory gestures of the velum in two Wernicke aphasic patients were examined to compare their performances with those of an apraxic patient by means of the fiberoptic technique. In contrast to the marked variability in the apraxic performance in terms of velum height and segmental duration, the two fluent aphasic subjects showed a relatively high degree of consistency in velar movements throughout several repetitions of nonsense syllables and meaningful words. In addition, both patients exhibited a normal pattern of anticipatory coarticulation. Analyses of the velar movement patterns during the speech-sound error processes of both patients suggested that these errors were not due to an impairment at the level of articulatory programming but to an error in the selection of a target phoneme.