Investigating Effects of Inhibitory Control Training for Insomnia Disorder Phenotypes

Insomnia disorder (ID) presents in two forms based on total sleep duration (TST): one with short sleep (ISSD) and another with normal sleep (INSD). Research suggests that ISSD, characterized by TST less than 7 hours, may be linked to impaired inhibitory function, potentially affecting cortical inhibition. This study aimed to evaluate response inhibition in these two insomnia phenotypes and the effects of response inhibition training.

The study involved 81 patients with ID (categorized into ISSD and INSD) and 22 healthy controls (HC). Participants underwent assessments using various clinical measures, including the Pittsburgh Sleep Quality Index (PSQI) and cognitive tasks. Each ID group was further divided into training and control sub-groups, with the training group engaging in an Adaptive Go/NoGo task designed to enhance inhibitory control over three weeks.

The results showed the following:

• Patients with ISSD experienced longer sleep latency and shorter wakefulness and light sleep durations compared to INSD. 
• No significant sleep differences were found between INSD and HC. 
• Post-training, ISSD participants showed improvements in PSQI and Insomnia Severity Index (ISI) scores. 
• Both INSD sub-groups experienced significant reductions in PSQI, ISI, and cognitive arousal scores after training.

To summarize, ISSD is associated with impaired response inhibition, indicative of disrupted cortical inhibition, while INSD may be linked to cognitive-emotional factors. Response inhibition training effectively improves sleep disorders in ISSD, offering promising directions for targeted interventions in ID.

Source: Zhang H, Lv Z, Chen H, Tang Z, Lei X. The benefit of inhibitory control training for insomnia with short sleep duration phenotype: a pilot randomized trial. BMC Med. 2024 Dec 18;22(1):591. doi: 10.1186/s12916-024-03813-1. PMID: 39696383; PMCID: PMC11657586.