Decisional Impulsivity in Obesity

About this publication

This is an original, plain-language summary of a study published in the Malta Medical School Gazette in 2018. It is not a reproduction of the journal article.

The research examined whether adults living with obesity differed from healthy volunteers in how they gathered information before a decision, weighed immediate against delayed rewards, and waited before responding.

How the study was carried out

The researchers compared 30 adults with obesity, recruited from an eating-disorders service in Malta, with 30 age- and gender-matched healthy volunteers. Fourteen participants in the obesity group met criteria for binge eating disorder.

Participants completed a beads task to assess how much evidence they collected before deciding, a monetary-choice questionnaire to assess preferences for smaller immediate or larger delayed rewards, and a reaction-time task to measure premature responses. Questionnaires also assessed mood, anxiety and self-reported impulsivity.

Main findings

• Information gathering: the group with obesity viewed fewer beads before making a decision. This difference was statistically significant (p = 0.047), suggesting less evidence gathering in this particular task.
• Immediate versus delayed rewards: there was a trend towards a stronger preference for immediate rewards in the obesity group, but it did not meet the conventional threshold for statistical significance (p = 0.054).
• Waiting before responding: the study found no statistically significant group difference in premature responses (p = 0.691).

The results suggest that different aspects of impulsivity should be considered separately rather than treated as a single characteristic.

What the findings mean

The authors identified decision-making processes as an area for further research, including whether evidence gathering and consideration of future outcomes might help predict treatment outcomes or inform future interventions.

Important limitations

This was a small, observational comparison, not a treatment trial. The participants with obesity were recruited from one specialist service and had a high average body mass index, so the findings should not be assumed to apply to everyone living with obesity. The design cannot establish that impulsivity causes obesity or that changing decision-making would improve weight or health outcomes.

The delayed-reward result was inconclusive, and a non-significant difference in premature responding does not prove that the groups were equivalent. These group-level findings are not a judgement about any individual's self-control. This summary is for academic information and is not personal medical advice.

Citation and original source

Falzon Aquilina F, Grech A, Strelchuk D, Donamayor N, Agius M, Voon V. Decisional Impulsivity in Obesity. Malta Medical School Gazette. 2018;2(3):39-45.

Read the original journal article for the full methods, results and references.

Source reviewed: 6 November 2026.