Expectancies generated by melodic intervals: Perceptual judgments of melodic continuity

The present study tested quantified predictors based on the bottom-up principles of Narmour’s (1990) implication-realization model of melodic expectancy against continuity ratings collected for a tone that followed a two-tone melodic beginning. Twenty-four subjects (12 musically trained, 12 untrained) were presented with each of eight melodic intervals—two successive tones which they were asked to consider as the beginning of a melody. On each trial, a melodic interval was followed by a third tone, one of the 25 chromatic notes within the range one octave below to one octave above the second tone of the interval. The subjects were asked to rate how well the third tone continued the melody. A series of regression analyses was performed on the continuation ratings, and a final model to account for the variance in the ratings is proposed. Support was found for three of Narmour’s principles and a modified version of a fourth. Support was also found for predictor variables based on the pitch organization of tonal harmonic music. No significant differences between the levels of musical training were encountered.     

Expectancies generated by recent exposure to melodic sequences

In four experiments, we examined the effects of exposure to unfamiliar tone sequences on melodic expectancy and memory. In Experiment 1, 30 unfamiliar tone sequences (target sequences) were presented to listeners three times each in random order (exposure phase), and listeners recorded the number of notes in each sequence. Listeners were then presented target and novel sequences and rated how well the final note continued the pattern of notes that preceded it. Novel sequences were identical to target sequences, except for the final note. Ratings were significantly higher for target sequences than for novel sequences, illustrating the influence of exposure on melodic expectancy. Experiment 2 confirmed that without exposure to target sequences, ratings were equivalent for target and novel sequences. In Experiment 3, new listeners were assessed for explicit memory for target sequences following the exposure phase. Recognition of target sequences was above chance, but unrelated to expectancy judgments in Experiment 1. Experiment 4 replicated the exposure effect, using a modified experiment design, and confirmed that the effect is not dependent on explicit memory for sequences. We discuss the idea that melodic expectancies are influenced by implicit memory for recently heard melodic patterns.     

The subjective size of melodic intervals over a two-octave range

Musically trained and untrained participants provided magnitude estimates of the size of melodic intervals. Each interval was formed by a sequence of two pitches that differed by between 50 cents (one half of a semitone) and 2,400 cents (two octaves) and was presented in a high or a low pitch register and in an ascending or a descending direction. Estimates were larger for intervals in the high pitch register than for those in the low pitch register and for descending intervals than for ascending intervals. Ascending intervals were perceived as larger than descending intervals when presented in a high pitch register, but descending intervals were perceived as larger than ascending intervals when presented in a low pitch register. For intervals up to an octave in size, differentiation of intervals was greater for trained listeners than for untrained listeners. We discuss the implications for psychophysical pitch scales and models of music perception.     

An interval size illusion: the influence of timbre on the perceived size of melodic intervals

In four experiments, we investigated the influence of timbre on perceived interval size. In Experiment 1, musically untrained participants heard two successive tones and rated the pitch distance between them. Tones were separated by six or seven semitones and varied in timbre. Pitch changes were accompanied by a congruent timbre change (e.g., ascending interval involving a shift from a dull to a bright timbre), an incongruent timbre change (e.g., ascending interval involving a shift from a bright to a dull timbre), or no timbre change. Ratings of interval size were strongly influenced by timbre. The six-semitone interval with a congruent timbre change was perceived to be larger than the seven-semitone interval with an incongruent timbre change (interval illusion). Experiment 2 revealed similar effects for musically trained participants. In Experiment 3, participants compared the size of two intervals presented one after the other. Effects of timbre were again observed, including evidence of an interval illusion. Experiment 4 confirmed that timbre manipulations did not distort the perceived pitch of tones. Changes in timbre can expand or contract the perceived size of intervals without distorting individual pitches. We discuss processes underlying interval size perception and their relation to pitch perception mechanisms.     

Effect of different delayed auditory feedback intervals on a music performance task

The effects of 12 different delay intervals were studied in a musical task involving performance on an electronic organ. Disruption was found to occur to a degree comparable to similar studies involving verbal and rhythmic tasks under DAF. Maximal disruption was found with a delay of 0.27 sec, a value rather greater than that typically found to be most disruptive in speech. Three of the 12 Ss showed speeded performance under part of the range of DAF intervals, as compared with performance under immediate feedback; however, their performance also reached a peak of slowing at a delay of about 0.27 sec. No significant differences were found between male and female Ss’ performance. These findings were discussed without the context of control processes operating in music performance, and compared with the possibly analogous mechanisms of speech.     

Controlled attending as a function of melodic and temporal context

Melodic and rhythmic context were systematically varied in a pattern recognition task involving pairs (standard-comparison) of nine-tone auditory sequences. The experiment was designed to test the hypothesis that rhythmic context can direct attention toward or away from tones which instantiate higher order melodic rules. Three levels of melodic structure (one, two, no higher order rules) were crossed with four levels of rhythm [isochronous, dactyl (A U U), anapest (U U A), irregular]. Rhythms were designed to shift accent locations on three centrally embedded tones. Listeners were more accurate in detecting violations of higher order melodic rules when the rhythmic context induced accents on tones which instantiated these rules. Effects are discussed in terms of attentional rhythmicity.     

Editing (out) generated study words in a recognition exclusion task: Effects of response signal delay and generation procedure

Three experiments investigated participants' ability to exclude generated study words from "old" judgements on an exclusion task in which a response signal delay (RSD) was manipulated. In Experiment 1, words were generated by mentally conjoining components of two compound words, and a conjunction test condition was included (e.g., presentation of the lure checkpoint after studying checklist and needlepoint without generating the target). The exclusion error rate for generated words was higher than the conjunction error rate for a short RSD group but lower than the conjunction error rate for a long RSD group. The decrease in the familiarity effect across RSDs was extended to a conceptual cue generation procedure in Experiments 2 and 3, but an anagram generation procedure did not show similar evidence of recollection-based exclusions. The earliest indication of recollection-based editing of generated words occurred in a 2250-ms RSD (Experiment 3). An extension of a multi-factor transfer appropriate processing theory (deWinstanley, Bjork, & Bjork, 1996) of generation effects that incorporates influences of familiarity and recollection is advocated.     

Pigeons (Columba livia) associate time intervals with symbols in a touch screen task: evidence for ordinality but not summation

The present experiments examined whether pigeons can sum symbols that are associated with various temporal consequences in a touch screen apparatus. Pigeons were trained to discriminate between two visual symbols that were associated with 0, 1, 2, 3, 4, or 5 s either of delay to 4 s of hopper access (delay group) or duration of hopper access (reward group). In Experiment 1, the pigeons in both groups learned to select the symbol associated with the more favorable outcome, and they successfully transferred this discrimination to novel symbol pairs. However, when tested with 2 pairs of symbols associated with different summed durations, they responded on the basis of a simple response rule rather than the sum of the symbol pair. In Experiment 2, the reward group was presented with four symbols at once and was allowed to successively choose one symbol at a time. All pigeons chose the symbols in order from largest to smallest. This indicates that pigeons formed an ordered representation of symbols associated with different time intervals, even though they did not sum the symbols.     

The dual implication of dual affordance: stimulus-task binding and attentional focus changing during task preparation

In task switching experiments, comparing performance with bivalent stimuli (affording both tasks) to univalent stimuli (affording one task) confounds the need to change focus between dimensions and stimulus-task binding, because bivalent stimuli require focusing (and refocusing) but also appeared in the competing task before. To separate these influences, participants switched between vertical and horizontal judgments performed on bivalent (e.g., up-left) or univalent (e.g., left) actual locations or location words. In a critical condition involving bivalence without stimulus-task binding, actual locations and location words were each linked to a different task. Bivalence increased switch costs and preparation reduced switch costs only with bivalent stimuli. Stimulus-task binding affected performance in task repetitions, especially when little preparation time was afforded.     

Expectancies and memory for an emotional film fragment: a placebo study

This study investigated whether positive ("memory-enhancing") and negative ("memory-impairing") placebos may enhance and undermine, respectively, memory of a film fragment. After watching an emotional film fragment, participants were assigned to a "memory-enhancing" placebo group (n = 30), control group (n = 30), or "memory-impairing" placebo group (n = 30). Only participants who believed in the placebo effect were included in the analyses. In the positive placebo group, memory for the film fragment was better than that of participants who received negative placebos or control participants. Participants in the negative placebo group made more distortion errors than participants in the positive placebo or control group. Our findings show that people's expectancies about their memory may affect their memory performance. These results may have implications for both clinical practice and the legal domain.     

Distracted by distractors: eye movements in a dynamic inattentional blindness task

Inattentional Blindness (IB) occurs when observers engaged in resource-consuming tasks fail to see unexpected stimuli that appear in their visual field. Eye movements were recorded in a dynamic IB task where participants tracked targets amongst distractors. During the task, an unexpected stimulus crossed the screen for several seconds. Individuals who failed to report the unexpected stimulus were deemed to be IB. Being IB was associated with making more fixations and longer gaze times on distractor stimuli, being less likely to fixate the unexpected stimulus, and having lower working memory capacity than those who were not IB. Noticing the unexpected stimulus was not contingent upon fixating it, suggesting that some individuals processed the unexpected stimulus via covert attention. The findings support earlier research on working memory and IB. In addition, IBs were less efficient attentional allocators than those who were not IB, as reflected in their eye tracking of irrelevant distractors.     

Evaluation of a novel translational task for assessing emotional biases in different species

Changes in the processing of emotional information are key features of affective disorders. Neuropsychological tests based on emotional faces or words are used to detect emotional/affective biases in humans, but these tests are not applicable to animal species. In the present study, we investigated whether a novel affective tone discrimination task (ATDT), developed to study emotion-related behaviour in rats, could also be used to quantify changes in affective states in humans. To date, the methods used in human neuropsychology have not been applicable to animal experiments. Participants completed a training session in which they learnt to discriminate specific tone frequencies and to correctly respond in order to gain emotionally valenced outcomes, to obtain rewards (money), or to avoid punishment (an aversive sound clip). During a subsequent test session, additional ambiguous probe tones were presented at frequencies intermediate between the reward and avoidance paired tones. At the end of the task, participants completed self-report questionnaires. All participants made more avoidance responses to the most ambiguous tone cues, suggesting a bias towards avoidance of punishment. Individual differences in the degrees of bias observed were correlated with anxiety measures, suggesting the task’s sensitivity to differences in state anxiety within a healthy population. Further studies in clinical populations will be necessary to assess the task’s sensitivity to pathological anxiety states. These data suggest that this affective tone discrimination task provides a novel method to study cognitive affective biases in different species, including humans, and offers a novel assessment to study anxiety.     

Expectations and Realizations: The Role of Expectancies in Achievement Settings

High expectancies of success are widely assumed to have positive effects on performance in achievement situations. However, previous investigations have tended to ignore task difficulty or assume that expectancies affect performance in a linear fashion. In two investigations, we found that (a) expectancies were more closely related to performance at difficult tasks than easy tasks and (b) low expectancies produced the poorest levels of performance, but moderate and high expectancies were equally advantageous. The practical, methodological, and theoretical implications of these findings are considered.This research was supported by a Presidential Young Investigator Award from the National Science Foundation (SBR-8958211) to Jonathon D. Brown, and a National Science Foundation graduate fellowship to Margaret A. Marshall.     

Chunking by colors: assessing discrete learning in a continuous serial reaction-time task

Chunk learning (the process by which a sequence is learned and retrieved from memory in smaller, decomposed units of information) has been postulated as the main learning mechanism underlying sequence learning (Perruchet & Pacton, 2006). However, the evidence for chunk formation has been elusive in the continuous serial reaction-time task, whereas other continuous, statistical processes of learning account well for the results observed in this task. This article proposes a new index to capture segmentation in learning, based on the variance of responding to different parts of a sequence. We assess the validity of this measure by comparing performance in a control group with that of another group in which color codes were used to induce a uniform segmentation. Results showed that evidence of chunking was obtained when the color codes were consistently coupled to responses, but that chunking was not maintained after the colors were removed.     

Performance on a mirror-drawing task by non-right-handers

Left-, mixed-, and right-handed (each n = 10, N = 30) adolescent boys who were classified on the basis of a hand preference inventory performed a mirror-drawing task with a bilateral transfer of a skill paradigm. Participants' hand preference and the magnitude of bilateral transfer of skill were assessed in terms of errors committed and time taken to complete the mirror-drawing task. Mixed-handed participants exhibited significantly less habit interference for mirror drawing, and they performed the task significantly faster than the left-handers did; the group difference was not significant for the frequency of errors committed. These groups did not differ in terms of the magnitude of bilateral transfer of skill; the trend, however, showed that the transfer of skill was minimum in mixed-handers. These findings extend the theory that mixed-handed participants' inability to transfer motor skill from one hand to the other could be attributable to their lack of a clear pattern of lateralization. Their ability to perform well either at initial or later trials may be a function of less interference from their normal motor habits.     

Getting a tool gives wings: overestimation of tool-related benefits in a motor imagery task and a decision task

Two experiments examine whether people overestimate the benefits provided by tool use in motor tasks. Participants had to move different quantities of objects by hand (two at a time) or with a tool (four at a time). The tool was not within reach so participants had to get it before moving the objects. In Experiment 1, the task was performed in a real and an imagined situation. In Experiment 2, participants had to decide for each quantity, whether they preferred moving the objects by hand or with the tool. Our findings indicated that people perceive tool actions as less costly in terms of movement time than they actually are (Experiment 1) and decide to use a tool even when it objectively provides less time-based benefits than using the hands (Experiment 2). Taken together, the data suggest that people overestimate the benefits provided by tool use.