Cognitive Remediation in Patients With Bipolar Disorder: A Randomized Trial by Sequential tDCS and Navigated rTMS...

Area of Science:

• Neuroscience
• Psychiatry
• Neuromodulation

Background:

• Non-invasive brain stimulation (NIBS), including transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS), offers potential for treating cognitive impairment in bipolar disorder (BD).
• Optimizing combined tDCS and rTMS protocols to enhance neurocognitive effects and clinical outcomes in BD remains a research challenge.

Purpose of the Study:

• To investigate the efficacy of combining tDCS and neuronavigated rTMS targeting the V1 region on neurocognitive function in bipolar disorder patients experiencing depressive episodes.
• To evaluate the combined stimulation's impact on cognitive, emotional, and safety outcomes.

Main Methods:

• A randomized controlled trial involving 105 participants assigned to three groups: active tDCS-active rTMS, sham tDCS-active rTMS, and active tDCS-sham rTMS.
• A 3-week treatment protocol with 15 sessions (5 per week), consisting of tDCS followed by neuronavigated rTMS.
• Cognitive function and emotional state assessed using the THINC-integrated tool (THINC-it), Hamilton Depression Rating Scale, and Young Mania Rating Scale at baseline, post-treatment, and follow-up.

Main Results:

• The active tDCS-active rTMS group demonstrated significant improvements in Symbol Check (Time and Accuracy) at 3 weeks and Symbol Check Accuracy at 8 weeks compared to sham groups.
• Both active tDCS-active rTMS and sham tDCS-active rTMS groups showed significant improvement in depressive symptoms from baseline to 3 weeks.
• Neuroimaging revealed increased activity in the calcarine sulcus in the active tDCS-active rTMS group, suggesting neuroplastic changes in the visual cortex.

Conclusions:

• The combination of navigated rTMS with tDCS targeting the V1 region shows preliminary evidence as a potential treatment strategy for cognitive impairment and depressive symptoms in bipolar disorder.
• This combined NIBS approach may offer a novel therapeutic avenue for managing complex symptoms in BD patients.