Acute Administration of 10 mg Methylphenidate on Cognitive Performance and Visual Scanning in Healthy Adults: Randomised, Double-Blind, Placebo-Controlled Study

ObjectiveTo examine the effect of a low dose (10 mg) of methylphenidate on cognitive performance, visuospatial working memory (VSWM) and gaze behaviour capabilities in healthy adults.MethodsThis randomised, double-blind, placebo-controlled and crossover study examined the effects of 10 mg methylphenidate on cognitive performance, VSWM and gaze behaviour. Fixation duration and rate, gaze transition entropy, and stationary gaze entropy were used to quantify visual scanning efficiency in 25 healthy adults (36% female, mean +/- SD age = 33.5 +/- 7.8 years, BMI = 24.1 +/- 2.9 kg/m2). Attention, memory, and reaction time were assessed using the E-CogPro test battery.ResultsMethylphenidate significantly enhanced performance in numeric working memory tasks, reflected by reduced errors and increased accuracy relative to placebo. No significant changes were observed in other cognitive or visual scanning metrics.ConclusionsA low dose of methylphenidate improves limited domains of psychomotor speed and accuracy but does not affect visual scanning efficiency. This suggests limited usefulness as a general pro-cognitive aid and raises the possibility of a lower threshold of effect for measurable psychostimulant-induced changes to visual scanning behaviour. Further research is needed to explore these potential dose-response relationships and effects across diverse populations.Trial RegistrationACTRN12620000499987