Higher-order conditioning: From incidental associations to psychotic-like states

Speaker: Dr. Arnau Busquets Garcia 

Hospital del Mar Research Institute (Barcelona, Spain) 

Bibliography of the speaker: 

Arnau Busquets-Garcia  holds a degree in Human Biology from Pompeu Fabra University in Barcelona. He is an independent researcher at the Hospital Del Mar Research Institute in the Barcelona Biomedical Research Park (PRBB), where he heads the Cellular Mechanisms in Physiological and Pathological Behavior group. Previously, Arnau was a predoctoral researcher in the Neuropharmacology group at Pompeu Fabra University (Barcelona, 2009-2013), where he obtained his PhD, which received awards from Biogen-Idec and the Esteve Foundation. During his doctoral thesis, he specialized in how cannabis and the endocannabinoid system modulate brain functions. After completing his doctorate, Arnau spent six years in Dr. Giovanni Marsicano's laboratory at the NeuroCentre Magendie (Bordeaux, France), where he continued to study the effects of cannabis in animal models. In 2019, Arnau started his own research group that, by using behavioral, chemogenetic and imaging approaches, is trying to understand the brain circuits involved in social cognition, with a particular focus on higher-order conditioning. He is the author of more than 40 articles and has received a Starting Grant from the European Research Council (ERC), funding from the IBRO, and also from the Spanish Research Agency.   

Description of the general focus of the symposium: 

Understanding how the brain links events that were never directly paired is central to explaining complex learning, daily choices, belief formation, and the emergence of maladaptive perceptions. Higher-order conditioning, including sensory preconditioning, provides a powerful framework to investigate how neutral cues become meaningfully associated through incidental experience. This symposium brings together leading and emerging researchers who use cutting-edge behavioral models, computational approaches, and neurobiological techniques to uncover how such indirect associations shape cognition and how their dysregulation may contribute to psychotic-like states. 

Dr. Arnau Busquets-Garcia will open the session by presenting innovative paradigms that assess higher-order learning across multiple sensory modalities and social contexts. Expanding on the mechanistic level, Melie Talaron (University of Bordeaux & University of Sydney) will demonstrate how the hippocampus supports sensory preconditioning in rodents. Using refined behavioral assays combined with circuit-specific approaches, she will illustrate how hippocampal computations integrate neutral cue relationships and prepare downstream regions for later value assignment. Next, Unai Blanco (Neurocentre Magendie, Bordeaux) will discuss how incidental associations are encoded at the neural level. Drawing on in vivo imaging and targeted manipulations, he will reveal how distributed circuits capture relationships between seemingly irrelevant stimuli, offering insight into how associative maps are built spontaneously during experience. 

The symposium will turn toward translational relevance. Irene García Manzanares will present compelling findings showing that sensory preconditioning can serve as a sensitive behavioral window into cannabis-induced psychotic-like phenomena. Her data reveal how cannabinoids distort higher-order learning processes, providing a mechanistic bridge between incidental associations and vulnerability to psychotic symptoms. Finally, Dr. Natalia Zernicka-Glover (Francis Crick Institute, London) will share new results linking hallucination-like perception to neuromodulatory states and sleep. Her work highlights how altered internal models and disrupted inference may arise from aberrant associative processing, with direct implications for understanding the biological roots of hallucinations. 

Together, these talks offer a coherent and multidisciplinary view of higher-order conditioning from basic mechanisms to their pathological consequences. By integrating behavioral neuroscience, circuit analysis, and models of psychosis, this symposium will stimulate discussion across fields and showcase how studying incidental associations can illuminate both normal cognition and the origins of disordered perception. 

Brief description of the talk: 

Animals and humans adapt to changes in the environment through the encoding and storage of previous experiences. Although associative learning involving a reinforcer has been the major focus in the field of cognition, other forms of learning are gaining popularity as they are likely more relevant and frequent in human daily choices. Indeed, associations between non-reinforcing stimuli represent the most evolutionarily advanced way to increase the chances of predicting future events and adapting individuals’ behavior. Animals are also able to form these higher-order conditioning processes, but more research is needed to understand how the brain encodes and stores these complex cognitive processes. Arnau, a senior researcher who holds an ERC Starting Grant on this topic, will show different examples of higher-order conditioning paradigms in mice and how his lab is investigating the brain circuits involved.