Sushil K Jha

Assistant Professor of Neurobiology
School of Life Sciences,
Jawaharlal Nehru University
New Delhi-110067

Contact : 91-11-2670-4190

Fax : 91-011-2674-2558

E-mail: sushilkjha@mail.jnu.ac.in

web site: http://www.jnu.ac.in/Faculty/sushilkjha/

Research Interest:

Many sleep laboratories across the globe are trying to solve the mystery of sleep but still are far from triumph. It is a long debating issue whether sleep contributes to initiate the phenomenon called synaptic plasticity, which enables the brain to encode new information and store it properly. On these lines, we have shown recently the direct evidence that sleep enhances synaptic plasticity in the visual cortex during early development and that cortical activity during sleep plays an important role for such phenomenon. Also sleep, after training, appears to influence the consolidation of certain non-declarative memories (e.g. procedural skill learning) in humans and experimental animals. But there are a number of other types of memories, such as associative memory related fear conditioning and reward learning for which the role of sleep is yet to be determined.
My current goal is to investigate the role of sleep in associative memory; for example, fear condition and reward learning memory and its underlying mechanisms. By using pavlovian fear conditioning paradigm, we have shown that fear-conditioning learning augments the appearance of NREM sleep and suppress REM sleep. Further, by using classic model of in vivo synaptic plasticity, we have shown that sleep enhances synaptic plasticity (an underlying mechanism of memory consolidation).

Now I would like to address some functional questions about sleep, for example; [A] Does sleep enhances the consolidation of associative memory of fear conditioning and/or reward learning? [B] Does non-rapid eye movement (NREM) sleep facilitate the amygdala dependent cued fear conditioning and also reward learning memory while REM sleep facilitate hippocampus dependent associative memory.