Biology subjects

Basinski, K.

Publications and source records attributed to Basinski, K..

4 recordsLinked to original sources

bioRxiv2026

Auditory localization improves with aligned saccadic orienting

Animals actively sample the environment through movements of their sensory organs, yet whether these motor behaviors shape perception beyond the modality they directly control remains unresolved. In the auditory system, eye movements modulate neural activity from the auditory periphery to cortex, but their perceptual consequences have remained elusive. Here, we tested whether spontaneous eye movements exert a general influence on auditory perception or selectively interact with auditory computations involved in spatial orienting. Across four psychophysical experiments, participants freely explored natural scenes while performing auditory localization or pitch discrimination tasks. Brief sounds rapidly reorganized spontaneous gaze behavior, preferentially promoting large orienting saccades toward the sound source while suppressing saccades directed away. Critically, auditory localization systematically depended on the direction of spontaneous saccades: sound localization improved when saccades were directed toward the sound source and declined when saccades were directed away. No comparable relationship was observed during pitch discrimination despite closely matched auditory stimulation and visual exploration. These findings identify a selective coupling between saccadic behavior and auditory localization, providing a behavioral counterpart to the widespread oculomotor modulation observed throughout the auditory system. More broadly, our results suggest that the behavioral consequences of eye movements extend beyond vision, selectively engaging sensory computations linked to spatial orienting.

neuroscience↗

bioRxiv2025

Non-linear relationships between the auditory mismatch responses and the level of inharmonicity of complex sounds

Predictive processing accounts of perception suggest that the brain generates predictions about the incoming stimuli. Precision-weighting, is an important facet of predictive processing theories and has been extensively studied with mismatch responses using electroencephalography. Harmonicity is a feature of sound that is important for auditory perception and previous research has shown that it modulates the brains mismatch responses. Since inharmonic sound spectra contain more information (have higher information entropy), inharmonicity has been suggested to be involved in precision weighting. In this study we explored this issue by parametrically modulating the level of inharmonicity applied to synthetic sounds and recording mismatch responses (MMN and P3a) from healthy volunteers (N = 37). Our results show that a sigmoid function models the relationship between inharmonicity and MMN amplitude better than any linear or polynomial function. Furthermore, P3a amplitude has an inverted-U relationship with inharmonicity and peaks at inharmonicity levels just below the threshold for pitch discrimination. These results are consistent with the hypothesis that inharmonicity impairs F0 extraction above a certain threshold and does not serve as an index of precision in the auditory system.

neuroscience↗

bioRxiv2025

Inharmonicity enhances brain signals of attentional capture and auditory stream segregation

Harmonicity is an important feature for auditory perception. However, the neural substrates of processing inharmonic sounds remain unclear. Here, we systematically manipulated the harmonicity of sounds by introducing random jittering to their frequencies. Using electroencephalography, we studied the effect of inharmonicity on markers of auditory prediction errors -- mismatch negativity (MMN) and P3a -- in a roving oddball paradigm. Inharmonic sounds with a constant jittering pattern generated similar MMN and stronger P3a responses than harmonic sounds. In contrast, MMN responses became undetectable when the jittering pattern changed between consecutive sounds, suggesting that prediction errors are weighted by sequential but not spectral uncertainty. Interestingly, inharmonic sounds generated an object-related negativity, a response associated with the segregation of auditory objects. Our results suggest that inharmonicity induces the segregation of the auditory scene into different streams, captures attention, and gives rise to specific neural processes that are independent from the predictive mechanisms underlying sequential deviance detection.

neuroscience↗

bioRxiv2021

Enhanced mismatch negativity responses in harmonic compared to inharmonic sound sequences

Many natural sounds have frequency spectra composed of integer multiples of a fundamental frequency. This property, known as harmonicity, plays an important role in auditory information processing. However, the extent to which harmonicity influences the processing of sound features beyond pitch is still unclear. This is interesting because harmonic sounds have lower information entropy than inharmonic sounds. According to predictive processing accounts of perception, this property could produce more salient neural responses due to the brains weighting of sensory signals according to their uncertainty. In the present study, we used electroencephalography to investigate brain responses to harmonic and inharmonic sounds commonly occurring in music: piano tones and hi-hat cymbal sounds. In a multi-feature oddball paradigm, we measured mismatch negativity (MMN) and P3a responses to timbre, intensity, and location deviants in listeners with and without congenital amusia--an impairment of pitch processing. As hypothesized, we observed larger amplitudes and earlier latencies (for both MMN and P3a) in harmonic compared to inharmonic sounds. These harmonicity effects were modulated by sound feature. Moreover, the difference in P3a latency between harmonic and inharmonic sounds was larger for controls than amusics. We propose an explanation of these results based on predictive coding and discuss the relationship between harmonicity, information entropy, and precision weighting of prediction errors.

neuroscience↗