Vowel recognition: Inferences from studies of forward and backward masking

The recognition of brief vowels was studied in forward and backward masking tasks. In a series of experiments in which both target and mask parameters were systematically varied, two populations of subjects were identified. The majority (Nonmaskers) evidenced little masking at any interstimulus interval, while relatively fewer subjects (Maskers) evidenced backward masking (but not forward masking) over a 100-200 ms interval. Increasing target set size systematically increased masking for the Maskers but not for the Nonmaskers. Adding white noise to the targets increased the extent of masking for both groups. These results suggest (1) that masking does not impose a substantive constraint on vowel perception in running speech, and (2) that multiple strategies may exist for vowel recognition.     

Performing item- and subject-based analyses using ALICE

By using the program ALICE, we are able to perform subject- and item-based analyses of randomly ordered sets of data without the usual computational effort. The program allows us to transform data and combine, partition, or systematically manipulate them by simple, readily interpretable instructions. Of equal importance to us is the ease with which students and staff learn to use the program independently.     

Value systems of self and of Australian expatriates as perceived by indigenous students in Papua New Guinea

The Rokeach Value Survey was administered to 112 students at Goroka Teachers' College in Papua New Guinea. About half of the respondents ranked the values for self and the remainder ranked for Australian expatriates working in Papua New Guinea. There were several differences in the relative importance assigned to the terminal and instrumental values when the two types of ranking were compared. The students assigned more importance to general social and orthodox religious values, to some moral values, and to values involving rules of conduct related to status and authority when rankings were for self than when they were for expatriates. They ranked stimulus-seeking and materialistic values and values concerned with striving and competence higher in importance when rankings were for expatriates rather than for self. The average value systems (medians) for self and for expatriates were also compared for similarity with those obtained from groups previously tested in Papua New Guinea and in Australia. Similarity coefficients involving average rankings for self were much higher when comparisons were made within each nation than between the two nations. It was doubtful that the students were judging expatriate value systems accurately because similarity coefficients were close to zero (terminal values) and low positive (instrumental values) when average value systems for expatriates were compared with corresponding average rankings for self of Australians actually tested in Australia. Results were discussed in relation to the consequences of discrepancies in value systems between the indigenous population and expatriates and more generally as illustrating the importance of developing an ecology of values within and across nations.     

INCREASING EXTENDED CARE FACILITY RESIDENTS' ATTENDANCE AT RECREATIONAL ACTIVITIES WITH CONVENIENT LOCATIONS AND PERSONAL INVITATIONS1

Residents of extended care facilities generally exhibit a low level of attendance at recreational and therapeutic activities. Spatial arrangement of rooms, prompting, snacks, and small prizes have been suggested as factors that affect attendance. The present study examined the effects of an extensive system of prompts and the location of activity areas on the attendance of residents at a variety of activities. Twenty-six subjects were randomly selected from the ambulatory population of the facility. The first time each subject entered the activity room during the first 6 min of an activity session their name was recorded. Reliability measures were taken at 10 sessions, with a 95% mean agreement between observers. The variables examined were the amount of individualization of subjects (experimental group I: names announced versus experimental group 2: names not announced), room location (central or peripheral), use of names in announcements (activity only versus activity and group I names), and mode of announcement (PA system only versus PA system and in-person). A counter-balanced group design with repeated measures was used, with a randomly determined order of application of experimental treatments. An analysis of variance split plot 2.222 (Kirk, R. E. Experimental Design: Procedures for the Behavioral Science. Belmont, Ca.: Brooks-Cole, 1968.) of the level of subject attendance yielded significant main effects for room location, F(1, 24) = 5.47, p < 0.05, and type of announcement, F(1, 24) = 9.10, p < 0.01, and significant interactions for Individualization × Use of Names in Announcements, F(1, 24) = 5.57, p < 0.05, and Room Location × Mode of Announcement, F(1, 24) = 7.90, p < 0.01. The results indicate that using a centrally located room and announcement of resident names increases attendance at a variety of activities. The increased social and environmental interaction generated by activity attendance has potential therapeutic benefits for the residents involved. Furthermore, the kind of information reported here and by others should be taken into consideration by planners of a variety of group living facilities, ranging from nursing homes to residential treatment cottages.     

Future-time gradients for performance in test anxious individuals.

It was assumed that highly anxious individuals should have a negative goal gradient for future performance and that this negative goal gradient should be reduced as the test-anxiety dispositions of the individuals decreased. The results for 392 grade school (6th) students showed, as expected, that (a) the highly anxious individuals (n = 55) tended to decrease the number of problems solved correctly as a future goal (task) approached in time and that (b) the slopes of the negative goal gradients decreased as the test-anxiety dispositions decreased. When number of problems attempted was the measure of performance (c) ther was a tendency for Ss of low anxiety (n = 101) to increase their performance as the goal approached.     

Detection of a deficit in visual discrimination of pattern following lesions of anterior cortex: role of type of motivation.

6 albino rats were trained under appetitive motivation to perform diametrically opposed visual discriminations of pattern via opposite eyes. Small lesions were subsequently placed unilaterally in anterior neocortex. Following a period of post-surgical recovery, subjects were re-trained on the diammetrically opposed discriminations in alternating 10-trial blocks. Every subject made more post-surgical errors on the discrimination mediated by the eye contralateral to the lesion. Since albino rats have virtually complete decussation of the visual system, this indicates selective impairment in mediation of performance of pattern discrimination in the part of the lesioned hemispheres. Thus, findings previously obtained in studies involving aversive motivation are general to appetitively motivated tasks.     

Effects of postresponse visual stimuli on visual discrimination learning in the rhesus monkey

To learn more about the mechanism (or mechanisms) involved with postresponse stimulus processing during discrimination learning, a series of studies was conducted with monkeys to determine why the combined relevant and irrelevant stimuli impair learning more than irrelevant stimuli appearing alone. It was found that: (a) the greater size and complexity of the combination of stimuli were not responsible for the greater deficit, while the presence of the relevant stimuli (S^D and S^Δ) within the stimulus combination apparently was; (b) the more similar the postresponse irrelevant stimuli were to the relevant stimuli the greater the deficit that resulted; and (c) monkeys that had earlier learned to discriminate the relevant and irrelevant features of a combination showed no learning impairment when this same stimulus combination was later presented after the response during a new learning problem. These results were interpreted as evidence that: (1) processes associated with learning a discrimination problem do not end with the execution of a choice response; (2) postresponse stimuli produce greater impairment in discrimination learning when they are distorted versions of the relevant stimuli; and (3) the impairment resulting from postresponse irrelevant stimuli occurs primarily when this misinformation is processed and misperceived as being relevant to learning the discrimination problem.