Resting-state EEG default mode network connectivity and suicidal ideation in depressive disorders: a retrospective...

Area of Science:

• Neuroscience
• Psychiatry
• Public Health

Background:

• Suicide is a major public health concern.
• The transition from suicidal ideation (SI) to suicide attempts (SA) involves complex neurobiological processes.
• Understanding these mechanisms is crucial, especially in diverse psychiatric populations.

Purpose of the Study:

• To investigate if resting-state electroencephalography (EEG) functional connectivity patterns can differentiate between suicidal ideation and suicide attempts.
• To explore neurobiological markers associated with the ideation-to-action framework in suicide.

Main Methods:

• Analyzed resting-state EEG functional connectivity in 244 participants across three groups: non-suicidal, SI only, and SA.
• Focused on the default mode network (DMN) and inhibition network using source-level analysis.
• Examined findings in the full sample and a subgroup of individuals with depressive disorders.

Main Results:

• No significant group differences in EEG connectivity were found in the full sample after correction.
• In the depressive disorder subgroup, individuals with suicidal ideation/attempts (SI+SA) showed reduced theta-band DMN connectivity compared to non-suicidal individuals.
• No differences were observed between SI-only and SA groups, nor in the inhibition network.

Conclusions:

• Altered DMN connectivity is associated with suicidal ideation in depressive disorders.
• Inhibition network connectivity did not differentiate between SI and SA.
• Findings support the ideation-to-action framework and emphasize the importance of diagnostic context in suicide research.