UCL Division of Biosciences

Dr Arantza Barrios

Dr Arantza Barrios


Cell & Developmental Biology

Div of Biosciences

Joined UCL
1st Sep 2012

Research summary

One of the most fascinating properties of the brain is its ability to process one sensory stimulus into distinct, sometimes opposite, behavioural outputs. This is the basis of learning and decision-making, and what enables animals to couple behaviour with their ever-changing needs. 

My lab studies the mechanisms that provide neural circuits with this functional plasticity. We focus on three important factors that influence the way sensory information is processed: experiences, internal states and sexual dimorphism. 

Our experimental system is the nematode C. elegans, a genetic model organism with only 385 neurons (in males) and a high level of behavioural plasticity. We combine behavioral genetic screens, GCaMP recordings and optogenetics to dissect, at the molecular and single-cell level, how complex, integrative behavioural decisions arise from the dynamic properties of neural circuits. 

We study ethologically relevant innate and learned behaviours to address two main problems that all neural networks need to solve:

How are conflicting experiences integrated and resolved?

We have recently discovered a class of neuromodulatory interneurons in the brain of the C. elegans male, termed the MCMs (Mystery Cells of the Male) that are required for integration of rewarding experiences during learning.  The activity of the MCMs overrides the change in behavioural responses to tastants and odorants induced by aversive learning. We are currently dissecting how the activity of these neurons modifies information processing within a circuit for chemotaxis to produce a switch in behaviour from repulsion to attraction.

How are distracting stimuli filtered out under states of arousal?

We have found a conserved role for secretin neuropeptide signaling in the generation of behavioural states of arousal associated with innate motivational drives. In male worms, the secretin neuropeptide PDF suppresses food salience within the network for navigation to stimulate exploration away from food and in search of mates. We are now investigating the mechanisms by which food inputs are filtered out under a state of mate deprivation to allow males to go mate-searching.

Teaching summary

- Lecturer for the MSc in Neuroscience (ANATG002)

- Organiser of the Cell Biology course C. elegans practical (CELL2007 and CELL2008) 

- Personal tutor of Biomedical Sciences BSc students (PHOL1001)


1996 BSc in Biology – Universitat de Barcelona and Erasmus at King’s College London

2002  PhD in Developmental Biology- University College London - Supervisors Steve Wilson and Nigel Holder

2003-2004- Postdoctoral researcher -MRC LMCB - Supervisor Steve Nurrish

2005-2009- Postdoctoral researcher -Albert Einstein College of Medicine- Supervisor Scott Emmons

2009-2012- Postdoctoral Researcher- Rutgers University- Supervisor Maureen Barr

20012- Present - Research Associate/ Group Leader - University College London