Saadi Lahlou

senior fellow
EURIAS cohort 2013/2014
discipline Psychology
Chair in Social Psychology and Head of Department of Social Psychology in the London School of Economics

Research project

Context and Actuation of Selves: an Empirical Investigation


What makes us activate a specific aspect of our self at a given moment? What are the influences of context and situation in the role we take, on our behaviour? For example, when, and why, do people feel (or act) as “obese”? I address these questions with a new technique for introspection based on objective data.

Participants wear a miniature video camera (”subcam”) during normal activity for half a day. Actual activity is captured in high definition and stereo. In a second phase, participants are then confronted to their recordings. These first-person perspective cues trigger their episodic memory: participants provide verifiably accurate (and vivid) accounts of their mental processes at the time of the first recording.


I will use this effect to understand what aspects of their self they actuated at each moment, and what triggered this actuation (e.g. cues in the context, intentions in the subject…)

This should shed light on the nature of self, on mechanisms of social play in general, and in this case on stigma in particular. During the EURIAS fellowship I will focus on aspects of the self that may be problematic, by comparing a sample of obese to normal weight persons and to past obese (N=30).

Coding of tapes will measure the number of different selves taken in a day, and what triggers actuation of selves. Obese will be compared to normal and past obese. Preliminary work shows that ex-obese keep a “phantom body” (after bariatric surgery); how is this linked with self-actuation?



Saadi Lahlou is Chair in Social Psychology and Head of Department of Social Psychology in the London School of Economics. He holds a Ph.D. in Social Psychology from the Ecole des hautes études en sciences sociales in Paris and a Habilitation from Aix-Marseille University.


His current research focuses on the distribution of Determinants of Human Behaviour between the Physical Space, Mental Space, and Social Space; the Transfer of Knowledge in organizations with ICT; the Innovation Processes, especially involving participative design; and the Digital Ethnography. 

Selected publications


‘Insights from Societal Psychology: The Contextual Politics of Change’, with C. Howarth, & al., Journal of Social and Political Psychology, vol. 1, no. 1, 2013, pp. 364-513.


‘Yes, Ronald Reagan's Rhetoric Was Unique—But Statistically, How Unique?’, with C. Schonhardt-Bailey, & E. Yager, Presidential Studies Quarterly, vol. 42, no. 3, 2012, pp. 482-513.


Numériser le travail. Théories, méthodes et expérimentations, with V. Nosulenko & E. Samoylenko, Lavoisier, Paris, 2012.


Changing behaviours: representations, practices and context. The case of obesity, with I. Urdapilleta, Fond Français pour l'alimentation, Lyon, 2012.


System Innovation for Sustainability 4: Case Studies in Sustainable Consumption and Production - Energy Use and the Built Environment, (ed.), Greenleaf, Sheffield, 2011.


'How can we capture the subject's perspective? An evidence-based approach for the social scientist', Social Science Information, vol. 50, n° 3-4, 2011, pp. 607-655.


Designing User Friendly Augmented Work Environments, (ed.), Springer. Computer Supported Cooperative Work Series, London, 2010.


senior fellow
EURIAS promotion 2018/2019
Paris Institute for Advanced Study
discipline History Middle Ages
senior fellow
EURIAS promotion 2011/2012
Paris Institute for Advanced Study
discipline Anthropology
junior fellow
EURIAS promotion 2016/2017
Paris Institute for Advanced Study
discipline Political Science
junior fellow
EURIAS promotion 2018/2019
Paris Institute for Advanced Study
discipline Philosophy