Perceptual interactions between musical pitch and timbre.

These experiments examined perceptual interactions between musical pitch and timbre. Experiment 1, through the use of the Garner classification tasks, found that pitch and timbre of isolated tones interact. Classification times showed interference from uncorrelated variation in the irrelevant attribute and facilitation from correlated variation; the effects were symmetrical. Experiments 2 and 3 examined how musical pitch and timbre function in longer sequences. In recognition memory tasks, a target tone always appeared in a fixed position in the sequences, and listeners were instructed to attend to either its pitch or its timbre. For successive tones, no interactions between timbre and pitch were found. That is, changing the pitches of context tones did not affect timbre recognition, and vice versa. The tendency to perceive pitch in relation to other context pitches was strong and unaffected by whether timbre was constant or varying. In contrast, the relative perception of timbre was weak and was found only when pitch was constant. These results suggest that timbre is perceived more in absolute than in relative terms. Perceptual implications for creating patterns in music with timbre variations are discussed.     

Perceptual integration of timing and intensity variations in the perception of musical accents

The author investigated the detection of timing and intensity variations in tone sequences within the framework of perceptual independence or integration. The participants listened to sequences of tones that contained variations in timing, intensity, or both. Each participant tried to detect variations in the dimension that was declared relevant, which was either timing or intensity. The irrelevant dimension was held constant, or varied in a manner uncorrelated with the relevant dimension, or varied in a correlated manner. When the variations in the 2 dimensions were correlated, the correlation could be either positive (i.e., timing and intensity created accents in the same sequences) or negative (i.e., timing and intensity created accents in different sequences). Uncorrelated variation in the irrelevant dimension interfered with the detection of variations in the relevant dimension. In the case of a positive correlation between the 2 dimensions, the detection of variations was better than it was with the absence of variation in the irrelevant dimension only for participants who attended to timing. In the case of a negative correlation, the effect was the opposite. The results showed that timing and intensity accents were not processed by completely independent channels. Rather, information from the 2 dimensions combined at a late stage of processing.     

Perceptual capacitism: an argument for disjunctive disunity

Philosophical Studies - According to capacitism, to perceive is to employ personal-level, perceptual capacities. In a series of publications, Schellenberg (2016, 2018, 2019b, 2020) has argued that...     

Perceptual dependence: Evidence for an internal threshold

Ss were asked to make two forced-choice discriminations on each trial: in Experiment I, they had to tell on which side of the display a latter pair appeared and whether or not its members were identical; in Experiment II, to say where the pair appeared and whether it consisted of Xs or Os; in Experiment III, to say where a letter appeared and whether it rhymed with E; and in Experiment IV, to say whether a letter pair was presented and whether it was a word. In Experiment III, and for some Ss in Experiment I, the second discrimination was dependent on the first; that is, when the S was wrong on the first, he performed at chance level on the second. In Experiment IV, when Ss indicated that nothing was presented (with confidence), they performed at chance level on the recognition task; thus, recognition was dependent upon some information about the detection task. It is argued that perceptual dependence implies that a threshold state, a state in which the S has no information, exists for the dependent discrimination. One explanation of dependence assumes mediation of the dependent discrimination by a processing stage which succeeds stages mediating the other task.     

Perceptual scaling of synthesized musical timbres: Common dimensions,specificities, and latent subject classes

To study the perceptual structure of musical timbre and the effects of musical training, timbral dissimilarities of synthesized instrument sounds were rated by professional musicians, amateur musicians, and nonmusicians. The data were analyzed with an extended version of the multidimensional scaling algorithm CLASCAL (Winsberg & De Soete, 1993), which estimates the number of latent classes of subjects, the coordinates of each timbre on common Euclidean dimensions, a specificity value of unique attributes for each timbre, and a separate weight for each latent class on each of the common dimensions and the set of specificities. Five latent classes were found for a three-dimensional spatial model with specificities. Common dimensions were quantified psychophysically in terms of log-rise time, spectral centroid, and degree of spectral variation. The results further suggest that musical timbres possess specific attributes not accounted for by these shared perceptual dimensions. Weight patterns indicate that perceptual salience of dimensions and specificities varied across classes. A comparison of class structure with biographical factors associated with degree of musical training and activity was not clearly related to the class structure, though musicians gave more precise and coherent judgments than did nonmusicians or amateurs. The model with latent classes and specificities gave a better fit to the data and made the acoustic correlates of the common dimensions more interpretable.     

Memory for musical surface

This study of memory for music presented listeners with the first half of a short piano piece, O. Messiaen's Mode de valeurs et d'intensités. The piece is written according to a unique compositional principle that rigidly couples values of pitch (chroma and octave), duration, and dynamics. Listeners heard test excerpts, which were judged in terms of whether or not they might have come from the piece (either from the part they had heard or from the remainder of the piece). Even in the first block of trials, listeners were able to recognize segments from the part of the piece they had heard, suggesting surprisingly accurate memory for surface characteristics. Listeners were also able to generalize to the rest of the piece, accurately judging segments from the part of the piece they had not heard. However, performance on four kinds of transformed segments showed that the abstraction of a piece's surface characteristics adopts rather loose criteria. Even highly trained professional musicians informed of the compositional constraints before the experiment were not sensitive to the specific couplings between musical parameters. Rather, listeners appeared to be sensitive to contour (the pattern of increasing and decreasing pitch) and global correlations between pitch height and duration, dynamics, and interval size. Performance did not change with repeated hearings of the music.     

Perceptual classes established with forced-choice primary generalization tests and transfer of function

In Experiment 1, 20 college students learned two identity conditional discriminations using squares that differed in interior-fill percentage (called Fill23 and Fill77). A two-choice generalization test was then presented with number of test trials varied across groups of subjects. The test samples were 19 squares that ranged in fill value from 23% to 77%; the comparisons were squares with Fill23 and Fill77. The resulting gradients did not vary as a function of number of test trials. When the generalization test was repeated with a third comparison, "neither," the ranges of fill values that occasioned the exclusive selection of Fill23 or Fill77 were direct functions of the number of prior two-choice generalization trials. Finally, a disriminability test revealed that Fill23 and Fill77 were disciminable from the intermediate fill values. In Experiment 2, perceptual classes were established with 5 new students using 760 forced-choice generalization test trials. The student were then trained to select a different glyph in the presence of Fill23 and Fill77, followed by a three-choice generalization test in which the 19 fill stimuli served as samples and the two glyphs served as comparisons. The gradients ovelapped with those previously obtained during the three-choice generalization test that used Fill23 and Fill77 as comparisons. Finally, a discriminability test showed that many adjacent stimuli along thc fill dimension were discriminable from each other. Together, the results of both experiments suggest that ranges of fill-based stimuli functioned as members of perceptual classes, and each class also functioned as a transfer network for a new selection-based response.     

Infants' memory for musical performances

We evaluated 6- and 7-month-olds' preference and memory for expressive recordings of sung lullabies. In Experiment 1, both age groups preferred lower-pitched to higher-pitched renditions of unfamiliar lullabies. In Experiment 2, infants were tested after 2 weeks of daily exposure to a lullaby at one pitch level. Seven-month-olds listened significantly longer to the lullaby at a novel pitch level than at the original pitch level. Six-month-olds showed no preference but their low-pitch preference was eliminated. We conclude that infants' memory for musical performances is enhanced by the ecological validity of the materials. Moreover, infants' pitch preferences are influenced by their previous exposure and by the nature of the music.     

Mental representations for musical meter

Investigations of the psychological representation for musical meter provided evidence for an internalized hierarchy from 3 sources: frequency distributions in musical compositions, goodness-of-fit judgments of temporal patterns in metrical contexts, and memory confusions in discrimination judgments. The frequency with which musical events occurred in different temporal locations differentiates one meter from another and coincides with music-theoretic predictions of accent placement. Goodness-of-fit judgments for events presented in metrical contexts indicated a multileveled hierarchy of relative accent strength, with finer differentiation among hierarchical levels by musically experienced than inexperienced listeners. Memory confusions of temporal patterns in a discrimination task were characterized by the same hierarchy of inferred accent strength. These findings suggest mental representations for structural regularities underlying musical meter that influence perceiving, remembering, and composing music.     

Infant memory for musical experiences

Recent findings suggest that infants can remember words from stories over 2 week delays (Jusczyk, P. W., & Hohne, E. A. (1997). Infants' memory for spoken words. Science, 277, 1984-1986). Because music, like language, presents infants with a massively complex auditory learning task, it is possible that infant memory for musical stimuli is equally powerful. Seven-month-old infants heard two Mozart sonata movements daily for 2 weeks. Following a 2 week retention interval, the infants were tested on passages of the familiarized music, and passages taken from similar but novel music. Results from two experiments suggest that the infants retained the familiarized music in long-term memory, and that their listening preferences were affected by the extent to which familiar passages were removed from the musical contexts within which they were originally learned.     

Perceptual match effects in direct tests of memory: the role of contextual fan

The aim of the present study was to determine whether physical attributes of a memory representation would affect explicit memory performance and, if so, what type of factors would affect the size of a perceptual match effect. Subjects studied words in different, uncommon fonts and were later asked whether the word had been studied earlier. Words could be re-presented in the original font, a font studied with another word, or a font not seen earlier. In two additional experiments, we varied the numbers of words studied in the same unusual font (1 vs. 12 words per font). Recognition memory for the words was better if the test and study fonts matched, and this effect was larger for fonts not shared with other words. Moreover, old judgments were most likely to be classified as remember responses when words were re-presented in the same font when it had not been studied with other words. Although we found a significant effect of levels of processing, this factor did not interact with whether the font matched between study and test. These results are consistent with the predictions of the source of activation confusion model of memory and suggest that perceptual information operates according to the same memory principles as conceptual information.     

Perceptual processing of nontargets in an attention task

The capability of nontargets to qualitatively influence the semantic processing of coincident targets was investigated in three experiments. Subjects were aurally presented a series of word pairs and attempted to detect homonymic instances of a predesignated category (e.g., animals). The nontarget with which a target (e.g., ANT) was paired was appropriate (e.g., CRAWLING), inappropriate (e.g., UNCLE), or neutral (e.g., STRAW). Experiments 1 and 2 established that detection of targets can be facilitated by appropriate nontargets and inhibited by inappropriate ones. Thus, nontargets can influence the way in which targets are semantically represented. Experiment 3 showed that this effect is eliminated when subjects are precued as to the ear of entry of targets. Thus, precuing appears to curtail the perceptual processing of nontargets. The data run counter to theories that claim that focused attention does not entail the perceptual suppression of nontargets.     

Perceptual enhancement: persistent effects of an experience

Presenting a word enhances its later perceptual identification. This article focuses on the relation between this effect on perception and recognition memory. Prior experiments have revealed that perceptual enhancement is independent of recognition memory and have led to the two types of task being identified with separate memory systems. In contrast, the present experiments reveal parallel effects on the two types of task. Perceptual enhancement persists over days but, like recognition memory, is influenced by manipulations of retrieval conditions. I conclude that both perceptual and memory tasks rely on the retrieval of memory for whole prior processing episodes but can differ in terms of the number and nature of retrieval cues that they provide. I describe perception and memory within a common framework.     

Perceptual and linguistic interactions in speeded classification: tests of the semantic coding hypothesis

We tested the semantic coding hypothesis, which states that cross-modal interactions observed in speeded classification tasks arise after perceptual information is recoded into an abstract format common to perceptual and linguistic systems. Using a speeded classification task, we first confirmed the presence of congruence interactions between auditory pitch and visual lightness and observed Garner-type interference with nonlinguistic (perceptual) stimuli (low-frequency and high-frequency tones, black and white squares). Subsequently, we found that modifying the visual stimuli by (a) making them lexical (related words) or (b) reducing their compactness or figural 'goodness' altered congruence effects and Garner interference. The results are consistent with the semantic coding hypothesis, but only in part, and suggest the need for additional assumptions regarding the role of perceptual organization in cross-modal dimensional interactions.     

Perceptual learning for speech

Adult language users have an enormous amount of experience with speech in their native language. As a result, they have very well-developed processes for categorizing the sounds of speech that they hear. Despite this very high level of experience, recent research has shown that listeners are capable of redeveloping their speech categorization to bring it into alignment with new variation in their speech input. This reorganization of phonetic space is a type of perceptual learning, or recalibration, of speech processes. In this article, we review several recent lines of research on perceptual learning for speech.     

Perceptual scale expansion: an efficient angular coding strategy for locomotor space

Whereas most sensory information is coded on a logarithmic scale, linear expansion of a limited range may provide a more efficient coding for the angular variables important to precise motor control. In four experiments, we show that the perceived declination of gaze, like the perceived orientation of surfaces, is coded on a distorted scale. The distortion seems to arise from a nearly linear expansion of the angular range close to horizontal/straight ahead and is evident in explicit verbal and nonverbal measures (Experiments 1 and 2), as well as in implicit measures of perceived gaze direction (Experiment 4). The theory is advanced that this scale expansion (by a factor of about 1.5) may serve a functional goal of coding efficiency for angular perceptual variables. The scale expansion of perceived gaze declination is accompanied by a corresponding expansion of perceived optical slants in the same range (Experiments 3 and 4). These dual distortions can account for the explicit misperception of distance typically obtained by direct report and exocentric matching, while allowing for accurate spatial action to be understood as the result of calibration.