Obligatory “expectations” of expressive timing induced by perception of musical structure

Previous research has shown that, in a task requiring the detection of local deviations from mechanically precise timing in music, the relative detectability of deviations in different positions is closely related to the typical expressive timing pattern musicians produce when playing the music. This result suggests that listeners expect to hear music expressively timed and compensate for the absence of expressive timing. Three new detection experiments shed additional light on the nature of these timing expectations in musically trained listeners. Experiment 1 shows that repeated exposure to an atypically (but not unmusically) timed performance leaves listeners' timing expectations unaffected. Experiment 2 demonstrates that the expectations do not manifest themselves when listeners merely imagine the music in synchrony with a click track. Experiment 3, however, shows that the timing expectations are fully operational when the click track is superimposed on the music. These results reveal timing “expectations” to be an obligatory consequence of the ongoing auditory perception of musical structure. Received: 5 November 1996 / Accepted: 26 February 1997     

Distinguishing “slit” and “split”—an invariant timing cue in speech perception

The effect of speech rate on the distinction between “slit” and “split” was investigated. This distinction may be cued solely by a silent interval (SI) of sufficient duration between the [s] and the [1], and the boundary SI, at which “slit” and “plit” are perceived with equal probability, determined. In this experiment, although subjects showed good identification of the stimulus categories within the range of silent intervals used, no shift in the boundary SI was found for a twofold increase in speech rate. This finding is contrasted with most recent experiments which demonstrate “compensation” for changes in speaker characteristics, such as speech rate. Implications for models of speech perception are discussed.     

Shifts of criteria or neural timing? The assumptions underlying timing perception studies

In timing perception studies, the timing of one event is usually manipulated relative to another, and participants are asked to judge if the two events were synchronous, or to judge which of the two events occurred first. Responses are analyzed to determine a measure of central tendency, which is taken as an estimate of the timing at which the two events are perceptually synchronous. When these estimates do not coincide with physical synchrony, it is often assumed that the sensory signals are asynchronous, as though the transfer of information concerning one input has been accelerated or decelerated relative to the other. Here we show that, while this is a viable interpretation, it is equally plausible that such effects are driven by shifts in the criteria used to differentiate simultaneous from asynchronous inputs. Our analyses expose important ambiguities concerning the interpretation of simultaneity judgement data, which have hitherto been underappreciated.     

Syllabic vs segmental perception: On the inability to ignore “irrelevant” stimulus parameters

C. C. Wood and R S. Day have shown that reaction times (RT) to target segments within a syllable are significantly longer when the unattended segment in the syllable (either stop consonant or vowel) is varied randomly than when it is held constant. This has been taken as evidence for the perceptual unity of a stop con sonant-vowel syllable. However, this conclusion could be accepted with much more confidence if it could be shown that random variation in unattended segments does not cause an increase in RT if the unattended segments are not in the same syllable as the target segment. The present study, using bisyllabic natural speech stimuli, (1) reconfirms Wood and Day’s results, but (2) finds that random variation in unattended nontautosyllabic segments also results in significantly longer RTs than without nontautosyllabic variation. Segmental vs syllabic speech perception thus remains an open question.     

Action in perception? Empirical and philosophical arguments against the enactive approach to perception

This paper focuses on the epistemic conditions of visual perception, ie it concentrates on the question of what kind of knowledge is required for us in order to be able to see colours and shapes as spatial properties of things. According to contemporary theories of sensory perception that follow the tradition of George Berkeley, like Alva Noe's so-called enactive approach to perception, this type of visual perception requires a certain kind of implicit practical knowledge, namely implicit sensorimotor knowledge of the way sensory stimulation varies as the perceiver moves. Two objections are presented against this central claim of the enactive approach. First, empirical evidence from psychological research on children's cognitive and motor development suggests that visual content is entirely independent of sensorimotor knowledge. Second, the enactive approach gets involved in the characteristic problems of classical sense--datum theories by introducing the extremely problematic claim that the recognition of appearances is the epistemic starting point for the perception of things and their properties.     

An “outside-in” processing strategy in the perception of form

The discriminability of line segments in a number of different geometric forms was examined. The procedure used was to have one of the lines within a given form drawn thinner than the other lines. The location of the thin line varied randomly within the form, and subjects were required to detect its location. Three observations were made. First, outer line elements were discriminated more accurately than inner line elements. Second, the outer line advantage appeared to reflect an attentional strategy: By presenting inner and outer lines independently, and informing subjects in advance as to whether target lines would be in the inner or outer area of the form, the outer line advantage could be eliminated. Third, consonant with a global attentional strategy, and in opposition to any retinally tied, peripheral-to-central scanning process, an outer-line advantage was evident regardless of whether the fixation point was positioned within or outside the forms, or whether outer lines were more peripheral than inner lines.     

From “Block-Things” to “Time-Things”: Merleau-Ponty’s temporal ontology in part two of the phenomenology of perception

Continental Philosophy Review - Scholars such as Renaud Barbara and Bernhard Waldenfels and Regula Giuliani have emphasized time’s central role in Merleau-Ponty’s philosophy, and...     

Switching between memory and perception: Moving attention or memory retrieval?

Weber, Burt, and Noll (1986) estimated that the time needed to switch attention between memory and perception was around 300 msec. The first two experiments in the present paper estimated switching time using a variation of their task. Subjects reported aloud lists of six items. The items were read off a computer screen (perception), recited from memory, or reported alternately from the two sources. The data show that the switching-time estimate is influenced by input/output compatibility, response-initiation times, and memory load. When these factors were controlled, estimated switching time dropped to around 100-150 msec. The data suggest, however, that the switch from perception to memory might be slower than the switch from memory to perception, which would invalidate the formula used to compute switching time. Experiment 3 tested the time for a single switch from perception to memory and a single switch from memory to perception by restricting report to one pair of items in the list. When the to-be-reported pair was precued, estimated switching time dropped to zero. When the pair was not precued, the memory-to-perception switching time remained at zero, but the perception-to-memory time was more than 400 msec. The pattern of results forced a reconceptualization of the task in terms of memory retrieval rather than attention switching. The attention-switching times appear to reflect processes required to select items from memory.     

Temporal stability of rhythmic tapping “on” and “off the beat”: A developmental study

This study, following a dynamic pattern approach, examines age-related differences in the stability of unimanual rhythmic perception-action patterns. Thirty-six children, aged 7, 9, and 11 years, attempted to synchronize their finger tapping to the beats of an auditory metronome, either “on the beat” (i.e., in-phase coordination), or “off the beat” (i.e., antiphase coordination). The temporal stability of these perception- action patterns was measured by the variability of the relative phase between taps and auditory events and by the critical frequency, that is, the frequency at which a loss of stability was observed when the metronome frequency was increased. Age-related differences in stability were found for both relative phase variability and critical frequency. These findings suggest that the relative phase dynamics underlying perception-action coordination patterns change with age in the direction of an increased temporal stability. Received: 29 June 1998 / Accepted: 15 December 1998     

Is the interference between memory processing and timing specific to the use of verbal material?

Increasing load in a memory task performed simultaneously with a timing task shortens perceived time, an effect that has been observed previously with memory tasks using verbal material. The present experiments examine whether two similar memory tasks, one in which verbal material is used and another one in which nonverbal material is used, would produce similar interference effects on concurrent time reproduction. In Experiment 1, the number of nonverbal stimuli (pseudo‐random dot patterns) was manipulated in a memory task performed while a temporal interval to be reproduced was encoded. Reproductions shortened proportionally to the duration of memory processing executed during time estimation. Verbal stimuli (consonants) were used in Experiment 2 in otherwise identical experimental conditions. Effects observed in Experiment 2 were comparable to those obtained in Experiment 1. Taken together, these results support the notion that interference from memory tasks on concurrent time estimation is not determined by the specific type of material processed in memory, but instead by the duration of memory processing.     

Is the interference between memory processing and timing specific to the use of verbal material?

Increasing load in a memory task performed simultaneously with a timing task shortens perceived time, an effect that has been observed previously with memory tasks using verbal material. The present experiments examine whether two similar memory tasks, one in which verbal material is used and another one in which nonverbal material is used, would produce similar interference effects on concurrent time reproduction. In Experiment 1, the number of nonverbal stimuli (pseudo-random dot patterns) was manipulated in a memory task performed while a temporal interval to be reproduced was encoded. Reproductions shortened proportionally to the duration of memory processing executed during time estimation. Verbal stimuli (consonants) were used in Experiment 2 in otherwise identical experimental conditions. Effects observed in Experiment 2 were comparable to those obtained in Experiment 1. Taken together, these results support the notion that interference from memory tasks on concurrent time estimation is not determined by the specific type of material processed in memory, but instead by the duration of memory processing.     

Individual differences in the vibrotactile perception of a “simple” pattern set

Discriminative capacities for vibrotactile spatiotemporal patterns were examined in 62 college students with three tasks: identification, masking, and discrimination of the letters “X” and “O” presented tactually on the Optacon, a reading machine for blind persons. Individual differences in performance and interrelations among scores within and across paradigms were explored. In identification, most persons quickly achieved consistently better than 90% performance, but others failed to identify the patterns above 80%, even after prolonged training. The same performance variance was found when the task was repeated by 23 Naval student pilots. Masking and discrimination measured susceptibility to interference when patterns followed one another closely in time. The resulting functions were typical, with poorest performance at short stimulus onset asynchronies. Again, a wide range of performance was seen. Individual performance, however, appeared to be consistent across tasks, suggesting that abilities in a variety of pattern-perception tasks might be predictable.     

From the Historical Reformation to the “Digital Reformation”

This article analyzes the challenges presented for contemporary theological thinking by the current shifts in communication, starting from the concept of a “digital reformation” as a counterpart to the theological revolution that occurred with the historical Reformation. It goes on to consider how processes of communication on the Internet require us to rethink certain theological categories – from the new and renewed ways of constituting and manifesting theological knowledge within the digital environment through the emergence of new loci, subjects, and theological syntheses. We conclude that the challenges of contemporary digital culture and the need for a connected theology mean that theology, as a field of knowledge, requires a new theological synthesis.     

Selecting the “Best” Factor Structure and Moving Measurement Validation Forward: An Illustration

Despite the broad literature base on factor analysis best practices, research seeking to evaluate a measure's psychometric properties frequently fails to consider or follow these recommendations. This leads to incorrect factor structures, numerous and often overly complex competing factor models and, perhaps most harmful, biased model results. Our goal is to demonstrate a practical and actionable process for factor analysis through (a) an overview of six statistical and psychometric issues and approaches to be aware of, investigate, and report when engaging in factor structure validation, along with a flowchart for recommended procedures to understand latent factor structures; (b) demonstrating these issues to provide a summary of the updated Posttraumatic Stress Disorder Checklist (PCL–5) factor models and a rationale for validation; and (c) conducting a comprehensive statistical and psychometric validation of the PCL–5 factor structure to demonstrate all the issues we described earlier. Considering previous research, the PCL–5 was evaluated using a sample of 1,403 U.S. Air Force remotely piloted aircraft operators with high levels of battlefield exposure. Previously proposed PCL–5 factor structures were not supported by the data, but instead a bifactor model is arguably more statistically appropriate.     

New evidence for “closure” in perception

A new criterion of perceptual grouping (Gillam, 1972), namely, that contours appear to reverse together under conditions of depth ambiguity, was used to test for the reality of “closure” and explore the parameters determining its degree. It was found that contours which would form a closed space but for a linear gap were responded to as a unit to a degree which decreased monotonically with gap size. Neither “proximal” nor “distal” gap was found to be the sole determinant of closure. Several levels of processing appear to be involved.