Abstract
Animal behaviour is dictated by internal variables, such as the need to feed, drink, survive or reproduce. Together with external stimuli and past experiences, these variables define an animal’s state, or emotional state, that determines a repertoire of appropriate behaviours given the specific circumstances. Although it is understood that the emotional state of an animal is a function of the ongoing brain network configuration, it remains largely unknown how the corresponding brain-wide configurations are generated and how they define emotional states and behaviour. Key to understanding of the neurobiological principles underlying emotional states is a distributed brain system, historically termed the “limbic system”, that processes emotional, metabolic and social stimuli. One of the key hubs of the “limbic system” is the amygdala, a set of subcortical nuclei highly interconnected with many brain areas and classically implicated in associative conditioning.
In my talk, I will discuss the general neurobiological principles underlying the generation of emotional states across different behavioural paradigms by focusing on the mouse amygdala. I will present recent experiments longitudinally imaging neural calcium dynamics across different environments in freely moving mice engaged in exploratory or learned instrumental behaviours demonstrating that changes in the activity of major, non-overlapping populations of amygdala principal neurons predict switches between behavioural states and that these state signals are tightly correlated with an animal’s learned expectations. The amygdala broadcasts state information via several output pathways to larger brain networks, and sensory responses in BA occur independently of behavioural state encoding. Thus, the brain processes external stimuli and internal states orthogonally, which may facilitate rapid and flexible selection of appropriate, state-dependent behavioural responses.
Biography
Andreas Lüthi obtained his PhD in Neurobiology at the University of Basel, Switzerland. After postdoctoral stays in Bristol, UK and in Zurich, Switzerland, he established his own research group in 2000, initially at the Biozentrum of the University of Basel and then at the Friedrich Miescher Institute for Biomedical Research. His lab addresses how neuronal circuits can generate behavior with a particular emphasis on synaptic, cellular and circuit mechanisms underlying learning and memory using classical conditioning as a model system. Recently, his lab became interested in the neuronal network mechanisms underlying the generation of emotional states.