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Biology subjects

Patel, A. D.

Publications and source records attributed to Patel, A. D..

3 recordsLinked to original sources

Within-species differences in vocal production learning in a songbird are associated with differences in flexible rhythm pattern perception

Humans readily recognize a familiar rhythmic pattern, such as isochrony (equal timing between events) across a wide range of rates. This ability reflects a facility with perceiving the relative timing of events, not just absolute interval durations. Several lines of evidence suggest that this ability is supported by precise temporal predictions that arise from forebrain auditory-motor interactions. We have shown previously that male zebra finches, which possess specialized auditory-motor networks and communicate with rhythmically patterned sequences, share our ability to recognize isochrony independent of rate. To test the hypothesis that flexible rhythm pattern perception is linked to vocal learning, we ask whether female zebra finches, which do not learn to sing, can also recognize global temporal patterns. We find that non-singing females can flexibly recognize isochrony but perform slightly worse than males on average. These findings are consistent with recent work showing that while females have reduced forebrain song regions, the overall network connectivity of vocal premotor regions is similar to that in males and supports predictions of upcoming events. Comparative studies of male and female songbirds thus offer an opportunity to study how individual differences in auditory-motor connectivity influence perception of relative timing, a hallmark of human music perception.

animal behavior and cognition↗

Mapping the contents of consciousness during musical imagery

Humans can internally represent auditory information without an external stimulus. When imagining music, how similar are unfolding neural representations to those during the original perceived experience? Can rhythmic motion influence the neural representation of music during imagery as during perception? Participants first memorized six one-minute-long instrumental musical pieces with high accuracy. Functional MRI data were collected during: 1) silent imagery of melodies to the beat of a visual metronome; 2) same but while tapping to the beat; and 3) passive listening. During imagery, inter-subject comparison showed that melody-specific temporal response patterns were reinstated in right associative auditory cortices. When tapping accompanied imagery, the melody-specific neural patterns were extended to associative cortices bilaterally. These results indicate that the specific contents of conscious experience are encoded similarly during imagery and perception in the dynamic activity of auditory cortices. Furthermore, rhythmic motion can enhance the reinstatement of neural patterns associated with the experience of complex sounds, in keeping with models of motor to sensory influences in auditory processing.

neuroscience↗

Environmental rhythms orchestrate neural activity at multiple stages of processing during memory encoding: Evidence from event-related potentials

Accumulating evidence suggests that rhythmic temporal structures in the environment influence memory formation. For example, stimuli that appear in synchrony with the beat of background, environmental rhythms are better remembered than stimuli that appear out-of-synchrony with the beat. This rhythmic modulation of memory has been linked to entrained neural oscillations which are proposed to act as a mechanism of selective attention by amplifying early sensory responses to events that coincide with the beat. The current study aimed to further test this hypothesis by using event-related potentials (ERPs) to investigate the locus of stimulus processing at which rhythm temporal cues operate in the service of memory formation. Participants incidentally encoded a series of visual objects while passively listening to background, instrumental music with a steady beat. Objects either appeared in-synchrony or out-of-synchrony with the background beat. Participants were then given a surprise subsequent memory test (in silence). The timing of stimulus presentation during encoding (in-synchrony or out-of-synchrony with the background beat) influenced canonical ERPs associated with post-perceptual selection and orienting attention in time. Importantly, post-perceptual ERPs also differed according to whether or not participants demonstrated a mnemonic benefit for in-synchrony compared to out-of-synchrony stimuli, and were related to the magnitude of the rhythmic modulation of memory across participants. These results support two prominent theories in the field, the Dynamic Attending Theory and the Oscillation Selection Hypothesis, which propose that neural responses to rhythm act as a core mechanism of selective attention that optimize processing at specific moments in time. Furthermore, they reveal that in addition to acting as a mechanism of early attentional selection, rhythm influences later, post-perceptual cognitive processes as events are transformed into memory.

neuroscience↗