Research Projects

The following is the list of research projects, that I have worked on.

CRAFT: A framework for Deep transfer and semi-sup. learning

Transfer Learning, semi-supervised learning, Cognition Lab, IISc, 2024

State-of-the-art deep learning models are seldom as efficient in neuroscience as in domains with access to big data. A major reason is the rarity of large labeled datasets. Hence, the role of pre-trained models (transfer learning) and unlabeled data (semi-supervised learning) is important. We propose Contradistinguisher Regularized Adaptive FineTuning (CRAFT) of neural networks – a method for efficient transfer and semi-supervised learning.

Rescuing referral failures due to domain shift

Selective Classification, Domain Adaptation, Medical Imaging, Cognition Lab, IISc, 2024

Here, we address a major challenge with domain generalization – selective classification during automated medical image diagnosis. During selective classification, models must abstain from making predictions when label confidence is low, especially for samples that deviate from the training set (covariate shift). Such uncertain samples are referred to the clinician for further evaluation (“referral”). Yet, we see that even state-of-the-art deep learning models fail dramatically during referral when tested on medical images acquired from a different demographic or with different technology.

Predicting brain age with Supervised Domain Adaptation

Transfer Learning, Domain Adaptation, Brain age prediction, Cognition Lab, IISc, 2024

Increasing life expectancy and global median age make the population more susceptible to age-related neurological and cognitive disorders like mild cognitive impairments (MCI) and Alzheimer’s disease (AD). These disorders are known to greatly degrade the quality of life. Hence, detecting an early onset of these diseases becomes critical for the timely prognosis.

Predicting brain age with diffusion models

Generative Modeling, Brain age prediction, Cognition Lab, IISc, 2023

Diffusion Magnetic Resonance Imaging (dMRI) helps find the structural connectivity of the brain in the form of an undirected graph. Therefore, these graphs can be used as markers for brain age. But data scarcity makes it challenging for naïve deep-learning algorithms to succeed at this problem. Even larger datasets, like – Rush Alzheimer’s Disease Center (RADC) have around 750 scans. Therefore, data augmentation is one of the most viable solutions to this problem. The recent success of conditional stable (latent) diffusion models is not limited to just generating realistic natural images based on an input text (DALLE-2). They have been used successfully for stimulus reconstruction conditioned on the input fMRI activity. We propose the use of latent diffusion models for the generation of connectivity matrices conditioned on age. A realistic augmentation of the training set can reduce overfitting and help build a robust brain-age decoder from connectivity matrices.

Decoding Attention Signatures from EEG Data

Attention, Deep Learning, Cognition Lab, IISc, 2022

EEG data is extremely noisy, and heterogenous across humans. Variability increases further if the task design of a psychophysical changes. This project aims at answering the following:

Spoken Language Identification

SLID, Speech Signal Processing, Deep Learning, Jadavpur University, 2020

This aims at identifying language from speech data. Many Indian languages have similar phonemes, which makes it challenging to separate them. This project uses MFCC features to develop diffent algorithms to tackle this problem.

Text Normalization Using WFSTs

NLP, weighted finite state transducers, Voice Intelligence, SRIB, 2020

Text Normalization plays important role in all NLP pipeline. It is used to convert different representation of an entity into a single cannonical form. Weighted finite state transducers were used for this problem. This describes the technical details.

For more details about my projects, please look at my Resume (2022), and visit my Github account.