The Vocational Preference Inventory scores and environmental preferences

This study investigated the relationship between vocational interest as measured by the Vocational Preference Inventory and preferences of 175 undergraduates for structured or unstructured environments. Males having clear-cut preferences for structured situations had significantly higher Realistic-Conventional scores than those not having those preferences (p < .05). Additionally, males with structured preferences had significantly lower Social-Artistic scores (p < .025). Results for females were similar, but not statistically significant. Males also had significantly higher (p < .01) Realistic-Conventional scores than females. The significant relationships between VPI scores and preferences for structured and unstructured situations support Holland's contention that interest scores are expressions of personality needs.     

Effects of fundamental frequency contrast on discrimination and identification of dichotic CV syllables at various temporal delays

Dichotic CV syllables (identical and nonidentical pairs) were presented at nine temporal offsets between 0 and 500 msec. One task consisted in judging quickly whether the syllables in a pair were phonetically the same or different; the other task was to identify both syllables. The fundamental frequency (pitch) of the synthetic stimuli was either the same or different, and either predictable or unpredictable. The pitch variable had surprisingly little effect on the latencies of "same"-"different" judgments, and the expected "preparation" effect of pitch predictability was ba]rely present. Instead, there were strong effects on the frequencies of errors at short temporal delays, which suggests shifts or biases in the phonetic "same"-"different" criterion with context. A comparison with analogous errors in the identification task revealed identical patterns. Further analysis of identification errors showed no overall "feature sharing advantage": The direction of this effect depends on the kind of error committed. Also, a lag effect was found only in nonidentical pairs that received two identical responses. The results are discussed in the framework of a two-stage information-processing model. Effects of pitch are tentatively explained as biases from implicit (pitch) decisions at the auditory level on phonetic decisions in the presence of uncertainty. Four sources of errors are identified: fusion at the auditory level; "integration," confusions, and transpositions at the phonetic level.     

Developmental aspects of the generation effect

Children from Grades 2, 3, 5, and 7 (7.6, 9, 11, and 13 years of age, respectively) were required to generate or study exemplars of semantic categories (semantic orientation) or rhymes to stimulus words (phonetic orientation). Each child then participated in one of three retention tests: free recall, standard recognition, and rhyme recognition. The results indicated that the developmental emergence of the “generation effect” (C. E. McFarland, Jr., T. J. Frey, & D. D. Rhodes, Journal of Verbal Learning and Verbal Behavior, 1980, 19, 210–225; N. J. Slamecka & P. Graf, Journal of Experimental Psychology: Human Learning and Memory, 1978, 4, 592–604) was dependent on both encoding orientation and the type of retention task employed. A substantial generation effect first emerged (7-year-olds) for standard recognition in the semantic condition. A similar effect for recall was evident for 9-year olds, but not for younger children. Internal stimulus generation became a strong memory facilitator for phonetically encoded items at age 11 for standard recognition, but not until age 13 for recall. The results of the rhyme recognition test indicated that internal generation facilitated “transfer-appropriate processing” (C. D. Morris, J. D. Bransford, & J. J. Franks, Journal of Verbal Learning and Verbal Behavior, 1977, 16, 519–533) only for seventh graders (age 13). The processes underlying this developmental pattern were discussed.     

A versatile dispenser for commercial monkey chow reinforcement

A dispenser is described that can deliver a wide variety of foodstuffs of almost any consistency. Despite compact size, storage capacity is sufficient for several days of unattended operation. Computer-compatible logic allows flexible applications in animal housing facilities and experimental setups. Its application in delivering regular monkey chow as reinforcement in experiments is discussed.     

Stimulus dominance and ear dominance in the perception of dichotic voicing contrasts

Two studies were conducted to determine the effect of variations in voice onset time (VOT) on the perception of dichotic stop-consonant-vowel syllables contrasting in the voicing feature. The dichotic stimuli were partially fused, so that only a single response was required. Variations in VOT had a systematic effect on the probability of hearing the fused stimuli as voiced or voiceless. Changing the VOT of a voiceless stimulus had a larger effect than changing the VOT of a voiced stimulus. Unless one of the competing stimuli was close to the category boundary, the perceptual integration of their VOTs seemed to be roughly additive. The relative phase of the periodic portions of the stimuli had an unexpected effect on perception that remains to be explained. A number of subjects showed very strong right-ear dominance in these tests. The range and reliability of the laterality effects obtained, as well as certain other methodological features, make the present tests promising as tools for assessing individual differences in ear dominance.     

Two strategies in fricative discrimination

Synthetic noises from a [∫]-[s] continuum, followed by vocalic portions that influenced the location of the [∫]-[s] boundary in an identification test, were presented in AXB and fixed-standard AX discrimination tasks. The majority of naive subjects perceived these fricative-vowel syllables fairly categorically in both tasks; that is, discrimination functions followed the patterns predicted from identification scores and showed shifts contingent on the nature of the vocalic portion. However, two subjects achieved much better discrimination scores than the rest, and so did three experienced listeners and a group of less experienced subjects who had received some discrimination training in the AX task. These listeners, who (judging from their higher accuracy, pattern of responses, and subjective reports) successfully followed the nonphonetic strategy of restricting attention to the spectral properties of the fricative noise, were not influenced by different vocalic contexts. These results support the hypothesis that influences of vocalic context on fricative identification are tied to a phonetic mode of perception.     

Control of Expressive and Metronomic Timing in Pianists

In 12 tasks, each including 10 repetitions, 6 skilled pianists performed or responded to a musical excerpt. In the first 6 tasks, expressive timing was required; in the last 6 tasks, metronomic timing. The pianists first played the music on a digital piano (Tasks 1 and 7), then played it without auditory feedback (Tasks 2 and 8), then tapped on a response key in synchrony with one of their own performances (Tasks 3 and 9), with an imagined performance (Tasks 4 and 10), with a computer-generated performance (Tasks 5 and 11), and with a computer-generated sequence of clicks (Tasks 6 and 12). The results demonstrated that pianists are capable of generating the expressive timing pattern of their performance in the absence of auditory and kinaesthetic (piano keyboard) feedback. They can also synchronize their finger taps quite well with expressively timed music or clicks (while imagining the music), although they tend to underestimate long interonset intervals and to compensate on the following tap. Expressive timing is thus shown to be generated from an internal representation of the music. In metronomic performance, residual expressive timing effects were evident. Those did not depend on auditory feedback, but they were much reduced or absent when kinaesthetic feedback from the piano keyboard was eliminated. Thus, they seemed to arise from the pianist's physical interaction with the instrument. Systematic timing patterns related to expressive timing were also observed in synchronization with a metronomic computer performance and even in synchronization with metronomic clicks. These results shed light on intentional and unintentional, structurally governed processes of timing control in music performance.     

The roles of location specificity and masking mechanisms in the attentional blink

In a series of four experiments using rapid serial visual presentations of two target letters embedded in numeral distractors, with different numbers of display positions and with or without masking, we show that (1) the nonmonotonic, U-shaped attentional blink (AB) function, which occurs when all items are presented at the same display location, is eliminated in favor of a monotonic function when targets and distractors are presented randomly dispersed over four or nine adjacent positions; (2) the AB monotonicity is maintained with the spatially distributed presentation even when backward masks are used in all possible stimulus positions and when the location of the next item in sequence is predictable; and (3) the If-shaped AB is not due to position-specific forward or backward masking effects occurring at early levels of visual processing. We tentatively conclude that the U-shaped AB is primarily a function of the interruption of late visual processing produced when the item following the first target occurs at the same location. In order for the AB to severely disrupt performance, the item following the first target must be presented at the same location as the target so that it can serve both as a distractor and as a mask interrupting or interfering with subsequent visual processing.     

Relational invariance of expressive microstructure across global tempo changes in music performance: An exploratory study

Summary This study addressed the question of whether the expressive microstructure of a music performance remains relationally invariant across moderate (musically acceptable) changes in tempo. Two pianists played Schumann's Träumerei three times at each of three tempi on a digital piano, and the performance data were recorded in MIDI format. In a perceptual test, musically trained listeners attempted to distinguish the original performances from performances that had been artificially speeded up or slowed down to the same overall duration. Accuracy in this task was barely above chance, suggesting that relational invariance was largely preserved. Subsequent analysis of the MIDI data confirmed that each pianist's characteristic timing patterns were highly similar across the three tempi, although there were statistically significant deviations from perfect relational invariance. The timing of (relatively slow) grace notes seemed relationally invariant, but selective examination of other detailed temporal features (chord asynchrony, tone overlap, pedal timing) revealed no systematic scaling with tempo. Finally, although the intensity profile seemed unaffected by tempo, a slight overall increase in intensity with tempo was observed. Effects of musical structure on expressive microstructure were large and pervasive at all levels, as were individual differences between the two pianists. For the specific composition and range of tempi considered here, these results suggest that major (cognitively controlled) temporal and dynamic features of a performance change roughly in proportion with tempo, whereas minor features tend to be governed by tempo-independent motoric constraints.