Schizophrenia is a multifactorial disorder with a range of risk factors. Dysregulation in the systems involved in the stress response is a key component of its pathophysiology. Individuals at risk of developing schizophrenia exhibit hyperreactivity to stress and altered cognitive performance, both known as vulnerability markers. This study aims to determine whether stimulation of the prefrontal cortex can reduce reactivity to stress in unaffected siblings of patients with schizophrenia.

In a randomized, sham-controlled trial, 27 participants were assigned to receive either active (n = 14) or sham (n = 13) transcranial direct current stimulation (tDCS) over the prefrontal cortex for 30 min during exposure to an acute stressor. The stress response was measured biologically, via salivary cortisol levels, and cognitively, through a reality monitoring task, which serves as an intermediate cognitive vulnerability marker.

In contrast to the sham condition, active stimulation significantly reduced cortisol release in response to stress (F(9,216) = 1.972; p = 0.04) and prevented stress-induced impairment in reality monitoring (F(1,23) = 9.954; p = 0.004).

These findings suggest that tDCS should be a promising tool for reducing stress-induced biological and cognitive reactivity in a population at risk of schizophrenia.

Individuals with psychopathic traits display deficits in emotional processing. A key event-related potential component involved in emotional processing is the late positive potential (LPP). In healthy controls, LPP amplitude is greater in response to negative stimuli than to positive or neutral stimuli. In the current study, we aimed to compare LPP amplitudes between individuals with psychopathic traits and control subjects when presented with negative, positive or neutral stimuli. We hypothesized that LPP amplitude evoked by emotional stimuli would be reduced in individuals with psychopathic traits compared to healthy controls.

After a systematic review of the literature, we conducted a meta-analysis to compare LPP amplitude elicited by emotional stimuli in individuals with psychopathic traits and healthy controls.

Individuals with psychopathic traits showed significantly reduced LPP amplitude evoked by negative stimuli (mean effect size = −0.47; 95% CI −0.60 to −0.33; p < 0.005) compared to healthy controls. No significant differences between groups were observed for the processing of positive (mean effect size = −0.15; 95% CI −0.42 to 0.12; p = 0.28) and neutral stimuli (mean effect size = −0.12; 95% CI 0.31 to 0.07; p = 0.21).

Measured by LPP amplitude, individuals with psychopathic traits displayed abnormalities in the processing of emotional stimuli with negative valence whereas processing of stimuli with positive and neutral valence was unchanged as compared with healthy controls.