Musicians upweight pitch during prosodic categorization

Speech perception requires the integration of evidence from acoustic cues across multiple dimensions. Individuals differ in their cue weighting strategies, i.e. the weight they assign to different acoustic dimensions during speech categorization. In two experiments, we investigate musical training as one potential predictor of individual differences in prosodic cue weighting strategies. Attentional theories of speech categorization suggest that prior experience with the task-relevance of a particular acoustic dimensions leads that dimension to attract attention. Therefore, Experiment 1 tested whether musicians and non-musicians differed in their ability to selectively attend to pitch and loudness in speech. Compared to non-musicians, musicians showed enhanced dimension-selective attention to pitch but not loudness. In Experiment 2, we tested the hypothesis that musicians would show greater pitch weighting during prosodic categorization due to prior experience with the task-relevance of pitch cues in music. In this experiment, listeners categorized phrases that varied in the extent to which pitch and duration signaled the location of linguistic focus and phrase boundaries. During linguistic focus categorization only, musicians up-weighted pitch compared to non-musicians. These results suggest that musical training is linked with domain-general enhancements of the salience of pitch cues, and that this increase in pitch salience may lead to to an up-weighting of pitch during some prosodic categorization tasks. These findings also support attentional theories of cue weighting, in which more salient acoustic dimensions are given more importance during speech categorization.

Sensory Attenuation in Sport and Rehabilitation: Perspective from Research in Parkinson’s Disease

People with Parkinson’s disease (PD) experience motor symptoms that are affected by sensory information in the environment. Sensory attenuation describes the modulation of sensory input caused by motor intent. This appears to be altered in PD and may index important sensorimotor processes underpinning PD symptoms. We review recent findings investigating sensory attenuation and reconcile seemingly disparate results with an emphasis on task-relevance in the modulation of sensory input. Sensory attenuation paradigms, across different sensory modalities, capture how two identical stimuli can elicit markedly different perceptual experiences depending on our predictions of the event, but also the context in which the event occurs. In particular, it appears as though contextual information may be used to suppress or facilitate a response to a stimulus on the basis of task-relevance. We support this viewpoint by considering the role of the basal ganglia in task-relevant sensory filtering and the use of contextual signals in complex environments to shape action and perception. This perspective highlights the dual effect of basal ganglia dysfunction in PD, whereby a reduced capacity to filter task-relevant signals harms the ability to integrate contextual cues, just when such cues are required to effectively navigate and interact with our environment. Finally, we suggest how this framework might be used to establish principles for effective rehabilitation in the treatment of PD.

Perceptual Difficulty Persistently Increases Dominance in Binocular Rivalry—Even Without a Task

A major objective of perception is the reduction of uncertainty about the outside world. Eye-movement research has demonstrated that attention and oculomotor control can subserve the function of decreasing uncertainty in vision. Here, we ask whether a similar effect exists for awareness in binocular rivalry, when two distinct stimuli presented to the two eyes compete for awareness. We tested whether this competition can be biased by uncertainty about the stimuli and their relevance for a perceptual task. Specifically, we have stimuli that are perceptually difficult (i.e., carry high perceptual uncertainty) compete with stimuli that are perceptually easy (low perceptual uncertainty). Using a no-report paradigm and reading the dominant stimulus continuously from the observers’ eye movements, we find that the perceptually difficult stimulus becomes more dominant than the easy stimulus. This difference is enhanced by the stimuli’s relevance for the task. In trials with task, the difference in dominance emerges quickly, peaks before the response, and then persists throughout the trial (further 10 s). However, the difference is already present in blocks before task instruction and still observable when the stimuli have ceased to be task relevant. This shows that perceptual uncertainty persistently increases perceptual dominance, and this is magnified by task relevance.

Location Has a Privilege, but It Is Limited: Evidence from Probing Task Irrelevant Location

We investigated the extent of automaticity in location and orientation encoding by manipulating the task relevance of these features and assessing the amount of resources recruited by their encoding. Separate groups of participants were surprised with a location report trial (experiment 1) or an orientation report trial (experiment 2) at a point when only the item’s color had been task relevant. This was followed by control trials to assess the memory quality when location or orientation had become task relevant along with color. We found the surprise trial performance to be significantly worse than the first control trial for both location and orientation, but to a greater extent for orientation. Moreover, the control trials revealed reduced precision for color in both experiments. These results suggest that location encoding had much greater automaticity than orientation, but neither could be encoded in a completely automatic manner. All results were obtained with pre-registered experiments that replicated a separate set of initial experiments we performed. Our results are consistent with a graded, nondichotomous view of automaticity and have implications on the organizational structure of VWM representations.