Unravelling the mechanisms for attention-like behaviour in the central brain of Drosophila melanogaster
Human Cognitive and Systems Neuroscience
Final Report Abstract
Object-based attention is a cognitive function that describes the animal’s and human’s brain’s ability to prioritize one set of stimuli while ignoring other, less relevant stimuli. Human research suggests that the binding of diverse stimuli into one attended percept requires phase-locked oscillatory activity in the brain. Even the smallest brains in the animal world, such as insect brains display oscillatory brain activity during visual attention tasks. It has been unclear so far if neural oscillations in insects are selectively correlated to different features of attended objects or salient visual stimuli. In the present project, I worked on understanding how attention is generated in the fly brain, which structures are involved in attention and how can attention be modulated. I have addressed this question on a behavioural level and by recording local field potentials in the central complex of the Drosophila brain, a brain structure involved in visual navigation and decision making. I found that when presented with a battery of visual stimuli in a closed-loop virtual reality environment, Drosophila can display clear preferences and avoidance to certain salient visual stimuli. This behaviour could be manipulated by an optogenetic activation of a neuropeptide circuit involved in arousal and aggression, the dNPF circuit. This circuit projects to structures of the central complex, the Fan-shaped body. By recording in-vivo local field potential, during closed and open loop behavioural attention paradigms, I found that attention selectively increased the neural gain, or neuronal power of visual features associated with attended visual stimuli. Attention could be redirected to unattended objects by activation of the dNPF reward circuit. Further analysis showed that attention was associated with an increase in the 20- to 30-Hz oscillations that selectively locked on to temporal features of the attended visual objects. This resembles the function of human beta frequency range that regulates selective attention to salient visual stimuli in humans. My research suggests fundamental similarities of neuronal oscillatory activity in the brains across different species.
Publications
- (2018). Innate visual preferences and behavioral flexibility in Drosophila. Journal of Experimental Biology, 221(23)
Grabowska, M. J., Steeves, J., Alpay, J., Van De Poll, M., Ertekin, D., & van Swinderen, B.
(See online at https://doi.org/10.1242/jeb.185918) - (2020). Oscillations in the central brain of Drosophila are phase locked to attended visual features. Proceedings of the National Academy of Sciences, 117(47), 29925-29936
Grabowska, M. J., Jeans, R., Steeves, J., & van Swinderen, B.
(See online at https://doi.org/10.1073/pnas.2010749117)
