Biology subjects

Perrachione, T. K.

Publications and source records attributed to Perrachione, T. K..

3 recordsLinked to original sources

bioRxiv2021

Electrophysiological correlates of perceptual prediction error are attenuated in dyslexia

A perceptual adaptation deficit often accompanies reading difficulty in dyslexia, manifesting in poor perceptual learning of consistent stimuli and reduced neurophysiological adaptation to stimulus repetition. However, it is not known how adaptation deficits relate to differences in feedforward or feedback processes in the brain. Here we used electroencephalography (EEG) to interrogate the feedforward and feedback contributions to neural adaptation as adults with and without dyslexia viewed pairs of faces and words in a paradigm that manipulated whether there was a high probability of stimulus repetition versus a high probability of stimulus change. We measured three neural dependent variables: expectation (the difference between prestimulus EEG power with and without the expectation of stimulus repetition), feedforward repetition (the difference between event-related potentials (ERPs) evoked by an expected change and an unexpected repetition), and feedback-mediated prediction error (the difference between ERPs evoked by an unexpected change and an expected repetition). Expectation significantly modulated prestimulus theta- and alpha-band EEG in both groups. Unexpected repetitions of words, but not faces, also led to significant feedforward repetition effects in the ERPs of both groups. However, neural prediction error when an unexpected change occurred instead of an expected repetition was significantly weaker in dyslexia than the control group for both faces and words. These results suggest that the neural and perceptual adaptation deficits observed in dyslexia reflect the failure to effectively integrate perceptual predictions with feedforward sensory processing. In addition to reducing perceptual efficiency, the attenuation of neural prediction error signals would also be deleterious to the wide range of perceptual and procedural learning abilities that are critical for developing accurate and fluent reading skills.

neuroscience↗

bioRxiv2021

Similarity in sensory modality and information domain impair processing in a dual-task context: Evidence from behavior, pupillometry, and EEG

Project AbstractMaking sense of our environment requires us to extract simultaneous temporal and spatial information from multiple sensory modalities, particularly audition and vision. This sensory information can be stored in working memory (WM) to guide future actions, at which point it must be safeguarded against interference from ongoing sensory processing. Recent fMRI research has uncovered regions in human frontal cortex well-suited to coordinate this interplay between attention and WM for multisensory and multidimensional information. Which of these brain regions are engaged depends on both the sensory modality of the input and the information domain of the task, forming the basis of two complementary networks specialized for auditory/temporal and visual/spatial processing. Motivated by the functional specializations of these networks, we examined whether similarity in sensory modality and information domain modulates neural and perceptual interference between two concurrent tasks. Participants stored temporal or spatial information about auditory or visual stimuli in WM, and on some trials, performed an intervening temporal or spatial auditory task during WM retention. WM recall and auditory perceptual judgments were impaired when the two tasks relied on the same sensory modality and/or information domain. Pupil dilations were also larger in these conditions, indicating increased cognitive effort. Event-related potentials (ERPs) revealed a neural signature of domain-based interference that was masked by behavioral ceiling effects. These results demonstrate that modality and information domain jointly affect how task information is represented in WM, and concomitantly, how tasks engage the complementary auditory-temporal and visual/spatial cognitive control networks.

neuroscience↗

bioRxiv2021

Talker discontinuity disrupts attention to speech: Evidence from EEG and pupillometry

Speech is processed less efficiently from discontinuous, mixed talkers than one consistent talker, but little is known about the neural mechanisms for processing talker variability. Here, we measured psychophysiological responses to talker variability using electroencephalography (EEG) and pupillometry while listeners performed a delayed recall of digit span task. Listeners heard and recalled seven-digit sequences with both talker (single- vs. mixed-talker digits) and temporal (0- vs. 500-ms inter-digit intervals) discontinuities. Talker discontinuity reduced serial recall accuracy. Both talker and temporal discontinuities elicited P3a-like neural evoked response, while rapid processing of mixed-talkers speech led to increased phasic pupil dilation. Furthermore, mixed-talkers speech produced less alpha oscillatory power during working memory maintenance, but not during speech encoding. Overall, these results are consistent with an auditory attention and streaming framework in which talker discontinuity leads to involuntary, stimulus-driven attentional reorientation to novel speech sources, resulting in the processing interference classically associated with talker variability.

neuroscience↗