Personality and individual differences

Beliefs and no evidence

The majority of human beings are inclined to believe in things that are unfounded (without scientific evidence). Many of us believe, for example, in several gods, in the existence of supernatural powers, or in the efficiency of superstitious rituals and behaviours. Others willingly spend money on healing remedies whose effectiveness has not been scientifically verified. Lately, we became interested in the belief that we are able to detect lies, because in reality, we are not capable, we seem to guess.

Our research is interested in the links between such beliefs, personality, and cognitive biases. We are interested in the correlations, and the causality of these correlations.

Colour psychology

Colours shape our environment. Humans are rarely indifferent about them, in particular when they are salient. Popular opinion assumes that colours can even interact with our affective state, may it be in the form of mood changes or wellbeing. Given the current published scientific literature, we are very sceptical that general claims can be made regarding colour-affect relationships. So far, we miss a sufficient number of systematic investigations that adhere to common empirical standards. With our studies, we aim to enrich the scientific literature that will eventually inform on how colour can be linked to affect in a reliable and valid manner. Our different projects encompass three lines of expertise: i) experimental paradigms from cognitive psychology, ii) theoretical frameworks from emotion psychology, and iii) knowledge on colour science in everyday applications.

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The construct of impulsivity broadly regards those behaviours that are poorly conceived, prematurely expressed, unduly risky, or inappropriate to the situation and that typically result in undesirable consequences. Impulsivity is a central construct in various domains of psychology and neuropsychology, and constitutes a trans-diagnostic factor involved in a wide range of psychopathological disorders (e.g., addictive disorders, obsessive and compulsive disorders).

Representative research outcomes and related publications:

We have written the first French comprehensive handbook focusing on the definition, the conceptualization, the assessment, and the treatment of impulsive behaviours. This book targets the following audience: (1) French speaking clinicians (who not necessarily read English scientific literature), (2) researchers (especially those interested to have a complete picture of influential impulsivity models and who want to assess impulsivity in behavioural experiments), and (3) French-speaking bachelor and master students interested in impulsivity.

Billieux, J., Rochat, L., & Van der Linden, M. (2014). L’impulsivité : Ses facettes, son évaluation et son expression clinique. Bruxelles, Belgique : Mardaga.

We have created the first short version of one of the most used impulsivity questionnaire, i.e. the UPPS-Impulsivity Scale. This short scale has since been translated into many languages (e.g., Spanish, Italian, Chinese, Arabic) and adapted for the assessment of specific populations (e.g., children, traumatic-brain-injured patients).

Billieux, J., Rochat, L., Ceschi, G., Carré, A., Offerlin-Meyer, I., Defeldre, A.-C., Khazaal, Y., Besche-Richard, C., & Van der Linden, M. (2012). Validation of a short French version of the UPPS-P Impulsive Behaviour Scale. Comprehensive Psychiatry, 53, 609-615.

Related links :

We have participated in the elucidation of the cognitive and affective mechanisms underlying one specific impulsivity facet, namely “urgency”, which can be defined as the tendency to act rashly when faced to intense negative affect. Our findings, which have been since replicated in independent labs, shown that individuals with high urgency have greater difficulties to inhibit prepotent (or automatic) motor responses and are characterized by hazardous decision-making (assessed by laboratory tasks such as the Iowa Gambling Task). We also showed that heightened urgency is related with the involvement in a wide range of maladaptive and addictive behaviours (e.g., addictive use of smartphones, binge drinking, compulsive sexual behaviours).

Billieux, J., Gay, P., Rochat, L., & Van der Linden, M. (2010). The role of urgency and its underlying psychological mechanisms in problematic behaviours. Behaviour Research and Therapy, 48, 1085-1096.

Billieux, J., Van der Linden, M., & Rochat, L. (2008). The role of impulsivity in actual and problematic use of the mobile phone. Applied Cognitive Psychology, 22, 1195-1210.

In our brain, we have two hemispheres. These hemispheres do not have the same functions. In patients, we know about their specialization because of lesion studies. In healthy participants, we perform lateralized half-field studies. In our laboratory, we are investigating which functions are lateralized to which hemisphere. In particular, we developed a lateralized lexical decision task usable in different languages. We also evaluate the right hemisphere’s language and spatial abilities, assess the link between personality, creativity and hemispheric asymmetry. Recently, we also started to test the importance of right-handed gestures for language development in children.