Dr Isaac Bianco
Sir Henry Dale Fellow
Neuro, Physiology & Pharmacology
Div of Biosciences
- Joined UCL
- 1st Oct 2013
Main lab webpage: https://zebrafishucl.org/bianco-lab
The goal of our research is to understand how neural circuits control behaviour. How does the brain process sensory information, decide what actions to take and orchestrate the motor programmes that mediate a behavioural response? How are sensorimotor circuits organised at structural and functional levels and what do individual cells and neural populations contribute to information processing?
To address these questions, we are using larval zebrafish as a powerful systems model to examine the structure and function of neural circuits controlling specific behaviours. A key advantage of this animal is that it has a tiny, optically transparent brain, which enables us to use optical techniques to both monitor and manipulate neural activity at single-cell resolution throughout the nervous system. Moreover, by larval stages zebrafish have a rich behavioural repertoire and a well developed visual system. One of their most complex visually guided behaviours is hunting, which begins from only 5 days post-fertilisation. How does the larval brain categorise visual inputs as prey? What visual features are extracted and how does prey identification lead to the initiation of a hunting routine? During prey tracking, how are goal-directed swims and turns selected in response to a changing sensory input to close in on the target? How do factors such as motivational state and recent experience modulate the core sensorimotor pathway controlling this behaviour?
To investigate the circuit basis of this complex natural behaviour, we combine quantitative behavioural assays, functional calcium imaging, optogenetics and anatomical circuit tracing techniques. We have developed a virtual hunting assay for tethered larvae that can be combined with functional imaging allowing us to monitor network activity and behaviour simultaneously: larvae are partially restrained using gel and presented with prey-like visual cues on a miniature computer screen which they respond to with characteristic hunting behaviours. At the same time, we use two-photon laser scanning microscopy or light-sheet microscopy with transgenic fish expressing genetically encoded fluorescent calcium indicators to monitor neural activity throughout the brain. In this way we can monitor population activity across thousands of neurons, at sub-cellular resolution, whilst the animal performs a complex visuomotor task. In addition we are developing optogenetic methods to control the activity of neurons using light and thereby test the requirement for specific cells and activity patterns for the generation of downstream activity and motor outputs. These approaches, combined with mathematical modelling, are allowing us to understand the sensorimotor transformations that convert visual input into action. Our aim is to build models of complete sensorimotor circuits, from primary sensory tissues, such as the retina, through to the motor neurons that innervate muscles to effect a behavioural response.
- University of London
- PhD, Developmental Biology | 2008
- University of Cambridge
- BA, Natural Sciences | 2002