Effects of lithium on evoked potentials and performance during sustained attention

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Psychology

Background:

• Bipolar affective disorder, manic type, is often associated with cognitive impairments, particularly in attention and executive functions.
• Continuous Performance Test (CPT) is a standard neuropsychological tool for assessing sustained attention and impulsivity.
• Lithium is a primary mood stabilizer for bipolar disorder, but its precise effects on cognitive function require further elucidation.

Purpose of the Study:

• To investigate the effects of lithium treatment on cognitive performance and event-related potentials (ERPs) in patients with bipolar affective disorder, manic type.
• To examine how lithium influences reaction time, accuracy, and the late positive component (LPC) during a continuous performance test (CPT).

Main Methods:

• Administered two versions of the CPT (differing in complexity) to 15 patients with bipolar disorder, manic type, before and after lithium treatment.
• Measured reaction time, performance accuracy (errors of commission), and the late positive component (LPC) of ERPs concurrently with CPT performance.
• Utilized statistical analysis to compare pre- and post-treatment measures.

Main Results:

• Lithium treatment significantly decreased errors of commission on both CPT tasks, with a notable effect on the simpler task.
• Reaction time was significantly increased by lithium on the more difficult CPT task.
• Lithium significantly increased the amplitude of the late positive component (LPC) to target stimuli on the difficult CPT, suggesting enhanced attentional processing.

Conclusions:

• The findings support an attention-enhancing effect of lithium in bipolar disorder patients.
• Lithium appears to reduce the general tendency to respond impulsively to stimuli.
• These cognitive improvements, alongside mood stabilization, highlight lithium's multifaceted therapeutic role in managing bipolar disorder.