When and why are two emotional experiences similar to each other? Exploring the cognitive and neural mechanisms that underlie judgements of similarity between emotional experiences

Much of the meaning we extract from our experiences stems from their similarity to other experiences we have. Yet the experiences that we care most about are emotional experiences, such as winning a competition, succeeding in an exam, and passing an interview, or, by contrast, experiences of losing and failing. It is not known whether the mechanisms people use to judge the similarity between neutral stimuli apply for judgements of similarity between emotional stimuli. In fact, there are reasons to believe that people judge two emotional stimuli to be ‘similar’ even when they are quite different from each other, as long as they invoke the same feelings in us. For example, an image of a slumped drug addict in the streets of Tel-Aviv and an image of a child eating her dinner will be considered ‘different’ because they appear to have a very different (semantic) meaning. By contrast, the same image of an addict and an image of a starving Yemeni child may be evaluated as highly similar because they invoke similar negative feelings. This means that similarity judgments between two emotional stimuli may be based not only on semantic similarity, but also on ‘emotional similarity’. Importantly, recent studies have shown that over-generalization of the similarity between emotional experience is a key contributor to anxiety and PTSD, yet this work have mainly focused on the similarities between stimuli that lead to abnormal responses.

This project will explore the cognitive and neural mechanisms that underlie judgements of similarity between emotional experiences, a topic which has so far been neglected. We will : a) identify how the characteristics of emotional experiences inform their similarity metrics; b) unveil the underlying brain regions and mechanisms that contribute to judgements of similarity in emotional conditions; c) describe the changes in brain representations that occur during learning and maintenance and how they lead to later similarity judgement between emotional memories; d) explore the contribution of these mechanisms in post-traumatic-stress.
This multidisciplinary research project on emotional similarity seamlessly converges research interests and methodological expertise of the supervisory team. The student will be immersed in vibrant research groups (both in Manchester and Weizmann) and trained in: behavioural, imaging (fMRI ) and neurostimulation (TMS) methods.