Biology subjects

Joshi, S. N.

Publications and source records attributed to Joshi, S. N..

3 recordsLinked to original sources

bioRxiv2026

Cortical Spectral Dynamics in Flow and Frustration

Flow is a subjective state where tasks feel effortless and rewarding. It has been linked to distinct neural signatures, yet dynamics of these signals remain poorly understood. Here, we investigated spectral dynamics of brain activity in flow. We recorded electroencephalogram (EEG) data at positions AF7, AF8, TP9, and TP10 using a lightweight wearable device worn by ten adult participants while they completed a go-signal task and two stop-signal tasks. Task difficulty was continuously adjusted to induce either a sense of flow or frustration. Time-resolved spectral power and interregional coherence were extracted with continuous wavelet and wavelet coherence transforms; subjective flow was assessed after each block with the short-form Flow-State Scale. Subjective ratings confirmed that the flow and frustration conditions diverged in perception of flow. In the flow block, errors on stop trials coincided with pre-stimulus reductions in right temporoparietal gamma power and frontal beta and gamma power, alongside diminished frontotemporal gamma coherence. Comparison of flow and frustration revealed higher temporal beta power during frustration, consistent with greater cognitive load. Flow may involve finely balanced beta and gamma dynamics, and brief collapses of these rhythms may predict task errors. Spectral dynamics are actionable features for closed-loop engagement monitoring applications.

neuroscience↗

bioRxiv2024

Curriculum Learning: sequential acquisition of task complexity enhances neuronal discriminability

Curriculum Learning (CL) is a strategy where concepts with increasing complexity are acquired sequentially. Despite its widespread application, its putative neural mechanisms are poorly understood. In this study, using a multi-staged Go/No-Go auditory discrimination paradigm for mice, we show that CL improves and accelerates learning in a unidirectional way. By combining behavioral data with in vivo electrophysiological recordings of the auditory cortex, we demonstrate that neuronal discriminability is enhanced with sequential training. This improvement suggests that CL involves a convergence of common discriminable features in the auditory stimuli shared across tasks of different complexity. Our findings uncover specific properties of CL at the level of neuronal discriminability, distinguishing it from other forms of learning strategies.

neuroscience↗

bioRxiv2019

Perceptual weighting of binaural lateralization cues across frequency bands

The auditory system uses interaural time- and level differences (ITD and ILD) as cues to localize and lateralize sounds. The availability of ITDs and ILDs in the auditory system is limited by neural phase-locking and by the head size, respectively. Although the frequency-specific limitations are well known, the relative contribution of ITDs and ILDs in individual frequency bands in broad-band stimuli are unknown. To determine these relative contributions, or spectral weights, listeners were asked to judge the lateralization of stimuli consisting of eleven simultaneously presented 1-ERB-wide noise bands centered between 442 Hz and 5544 Hz and separated by 1-ERB-wide gaps. Interaural disparities were applied to each noise band and were roved independently on every trial. The weights were obtained using a multiple linear regression analysis. In a second experiment the effect of temporal context on the spectral weights was investigated. Ten of the noise bands were used as pre- and postcursors and listeners were asked to lateralize the stimuli. Results show that only the lowest- or highest frequency band received highest weight for ITD and ILD, respectively. Temporal context led to significantly enhanced weights given to the band without the pre- and postcursor. The weight enhancement could only be observed at low frequencies, when determined with ITD cues and for low and high frequencies for ILDs. Hence, the auditory system seems to be able to change the spectral weighting of binaural information depending on the information content. PACS43.64.-q {middle dot} 43.64.+r {middle dot} 87.19.lt {middle dot} 43.66.-x {middle dot} 43.66.+y {middle dot} 43.64.Bt

neuroscience↗