Spatial properties of perceived pitch: influence on reaching movements

Response orientation modulates pitch-space relationships: the ROMPR effect

Congruency between auditory and visuospatial stimuli has been previously shown to affect responses to multisensory stimulus pairs, and congruency between stimuli and response devices may play a role in response speed and accuracy. Across two experiments, we tested whether the accuracy and speed of pitch judgments were affected by a congruent or incongruent paired visual stimulus, and whether the relationship was modulated by response orientation. In Experiment 1, participants using a vertically (transversely) oriented keyboard demonstrated a large crossmodal vertical effect, but a minimal crossmodal horizontal effect. In contrast, Experiment 2 used a horizontally oriented keyboard, while also examining whether musical training impacts pitch judgments. As in the first experiment, we found an effect of response mapping on pitch judgments; these results suggest that vertical visual stimuli are processed automatically, while the effects of horizontal visual stimuli are decisional and require a compatible response orientation. Based on these findings, we propose an effect we call the ROMPR effect: response orientation modulates pitch-space relationships. Unexpectedly, non-musicians demonstrated significant ROMPR effects while trained musicians did not. We suggest that non-musicians are more likely to use visual information when making spatial location judgments of pitch: unlike musicians, they have not been trained to rely exclusively on auditory information during pitch processing. We also discuss alternative explanations of the data: namely, that there is a need to disambiguate audiovisual congruency from visual-response congruency with modulations of experimental design.

On the Relative Nature of (Pitch-Based) Crossmodal Correspondences

This review deals with the question of the relative vs absolute nature of crossmodal correspondences, with a specific focus on those correspondences involving the auditory dimension of pitch. Crossmodal correspondences have been defined as the often-surprising crossmodal associations that people experience between features, attributes, or dimensions of experience in different sensory modalities, when either physically present, or else merely imagined. In the literature, crossmodal correspondences have often been contrasted with synaesthesia in that the former are frequently said to be relative phenomena (e.g., it is the higher-pitched of two sounds that is matched with the smaller of two visual stimuli, say, rather than there being a specific one-to-one crossmodal mapping between a particular pitch of sound and size of object). By contrast, in the case of synaesthesia, the idiosyncratic mapping between inducer and concurrent tends to be absolute (e.g., it is a particular sonic inducer that elicits a specific colour concurrent). However, a closer analysis of the literature soon reveals that the distinction between relative and absolute in the case of crossmodal correspondences may not be as clear-cut as some commentators would have us believe. Furthermore, it is important to note that the relative vs absolute question may receive different answers depending on the particular (class of) correspondence under empirical investigation.

Seeing music: The perception of melodic 'ups and downs' modulates the spatial processing of visual stimuli

Musical melodies have "peaks" and "valleys". Although the vertical component of pitch and music is well-known, the mechanisms underlying its mental representation still remain elusive. We show evidence regarding the importance of previous experience with melodies for crossmodal interactions to emerge. The impact of these crossmodal interactions on other perceptual and attentional processes was also studied. Melodies including two tones with different frequency (e.g., E4 and D3) were repeatedly presented during the study. These melodies could either generate strong predictions (e.g., E4-D3-E4-D3-E4-[D3]) or not (e.g., E4-D3-E4-E4-D3-[?]). After the presentation of each melody, the participants had to judge the colour of a visual stimulus that appeared in a position that was, according to the traditional vertical connotations of pitch, either congruent (e.g., high-low-high-low-[up]), incongruent (high-low-high-low-[down]) or unpredicted with respect to the melody. Behavioural and electroencephalographic responses to the visual stimuli were obtained. Congruent visual stimuli elicited faster responses at the end of the experiment than at the beginning. Additionally, incongruent visual stimuli that broke the spatial prediction generated by the melody elicited larger P3b amplitudes (reflecting 'surprise' responses). Our results suggest that the passive (but repeated) exposure to melodies elicits spatial predictions that modulate the processing of other sensory events.

Pitch perception deficits in nonverbal learning disability

The nonverbal learning disability (NLD) is a neurological dysfunction that affects cognitive functions predominantly related to the right hemisphere such as spatial and abstract reasoning. Previous evidence in healthy adults suggests that acoustic pitch (i.e., the relative difference in frequency between sounds) is, under certain conditions, encoded in specific areas of the right hemisphere that also encode the spatial elevation of external objects (e.g., high vs. low position). Taking this evidence into account, we explored the perception of pitch in preadolescents and adolescents with NLD and in a group of healthy participants matched by age, gender, musical knowledge and handedness. Participants performed four speeded tests: a stimulus detection test and three perceptual categorization tests based on colour, spatial position and pitch. Results revealed that both groups were equally fast at detecting visual targets and categorizing visual stimuli according to their colour. In contrast, the NLD group showed slower responses than the control group when categorizing space (direction of a visual object) and pitch (direction of a change in sound frequency). This pattern of results suggests the presence of a subtle deficit at judging pitch in NLD along with the traditionally-described difficulties in spatial processing.

Implicit chord processing and motor representation in pianists

The aim of this paper is to assess the relevance of pitch dimension in auditory-motor interaction. Several behavioural and brain imaging studies have shown that auditory processing of sounds can activate motor representations, an effect which is however elicited only by action-related sounds, i.e., sounds linked to a specific motor repertoire. Music provides an appropriate framework for further exploration of this issue. Three groups of participants (pianists, non-pianist musicians and non-musicians) were tested with a shape decision task where left-hand and right-hand responses were required; each visual stimulus was paired with an auditory task-irrelevant stimulus (high-pitched or low-pitched piano-timbre chords). Of the three groups, only pianists had longer reaction times for left-hand/high-pitched chords and right-hand/low-pitched chords associations. These findings are consistent with an auditory-motor effect elicited by pitch dimension, as only pianists show an interaction between motor responses and implicit pitch processing. This interaction is consistent with the canonical mapping of hand gestures and pitch dimension on the piano keyboard. The results are discussed within the ideo-motor theoretical framework offered by the Theory of Event Coding (Hommel et al. in Behav Brain Sci 24:849-937, 2001).