Impaired social decision-making likely in suicide attempters with mental disorders

Individuals with mental disorders who attempted suicide were reported to have impaired or abnormal social decision-making, evidenced by neuro-electrophysiological activity, according to a study published in BMC Psychiatry.

“Neurocognitive attributes, such as decision-making, mediate thought-behavior relationships and may predispose individuals with suicide ideation to act on their thoughts and attempt suicide,” Shuang Liu, MS, PhD, of the Academy of Medical Engineering and Translational Medicine at Tianjin University in China, and colleagues wrote.

Seeking to assess neural responses of suicide attempters with mental disorders during a social decision-making exercise, researchers included 52 patients aged 18 to 65 years from the Tianjin Anding Hospital, half of whom had previously attempted suicide. Participants were matched by age and sex with 22 healthy controls.

Researchers recorded electroencephalography from all participants during the Ultimatum Game, a socioeconomic tool utilized to investigate responses to fair and unfair decision-making.

In addition, they also used a Chinese-based MINI 5.0 interview and self-report questionnaire to assess participants’ mental diagnosis and suicidal behavior, as well as event-related potential (ERP) and phase-amplitude coupling (PAC) to quantify neural activity. Researchers conducted Spearman correlation and logistic regression analyses to identify the risk factors of suicidal behavior.

According to ERP analysis, patients who attempted suicide had decreased P2 amplitude and prolonged P2 latency when receiving unfair offers. These individuals also exhibited greater negative-going feedback-related negativity to unfair offers vs. fair ones, which was not observed in those who had not attempted suicide and healthy controls. Further, those who attempted suicide registered a stronger fairness principle and a disregard for the cost of punishment in social decision-making.

Researchers additionally found that theta-gamma and beta-gamma PAC were involved in decision-making, with deficits in neural coordination in the frontal, central and temporal regions in those who had attempted suicide, which may indicate cognitive dysfunction in social interactions.

“The biomarkers developed in our work could be used as potential signals to bring new light to understand the neural mechanism of unfair decision-making in suicide attempters,” Liu and colleagues wrote.