Impaired volitional saccade control: first evidence for a new candidate endophenotype in obsessive–compulsive disorder

Abstract

Recent research suggests that patients with obsessive-compulsive disorder (OCD) have deficits in the volitional control of saccades. Specific evidence comes from increased latencies of saccadic eye movements when they were volitionally executed but not when they were visually guided. The present study sought to test whether this deviance represents a cognitive endophenotype. To this end, first-degree relatives of OCD patients as genetic risk carriers were compared with OCD patients and healthy controls without a family history of OCD. Furthermore, as volitional response generation comprises selection and initiation of the required response, the study also sought to specify the cognitive mechanisms underlying impaired volitional response generation. Twenty-two unaffected first-degree relatives of OCD patients, 22 unmedicated OCD patients, and 22 healthy comparison subjects performed two types of volitional saccade tasks measuring response selection or only response initiation, respectively. Visually guided saccades were used as a control condition. Our results showed that unaffected first-degree relatives and OCD patients were significantly slowed compared to healthy comparison subjects in volitional response selection. Patients and relatives did not differ from each other. There was no group difference in the visually guided control condition. Taken together, the study provides first evidence that dysfunctional volitional response selection is a candidate endophenotype for OCD.

Saccadic eye movement applications for psychiatric disorders

“…Kloft and colleagues56 investigated 22 unmedicated patients with OCD, 22 unaffected first-degree relatives of OCD patients, and 22 healthy volunteers. The study involved four task types: visually guided saccades and three different types of volitional saccade task: cued, un-cued, and free choice.…”

Dissociation of decision making under ambiguity and decision making under risk: A neurocognitive endophenotype candidate for obsessive–compulsive disorder

“…The first research that adopted this approach showed that OCD patients and their UFDR had deficits in motor inhibition (Chamberlain et al, 2007). Similar studies also found impairments in planning and working memory processes (Delorme et al, 2007), cognitive flexibility (Cavedini et al, 2010), volitional action generation (Kloft et al, 2013), performance monitoring (Riesel et al, 2011) and behavioral reversal (Viswanath et al, 2009) presented in both OCD probands and their UFDR. Moreover, to remove the effect of the drug treatment, a study by Rajender et al (2011) reported impaired set-shifting and inhibitory control in patients with drug-naïve OCD and their UFDR.…”

Risk genes, metabolic syndrome and eye tracking deficits in psychiatric diseases

“…Because of feasible impaired volitional saccade control in patients with obsessive-compulsive disorder (OCD), Kloft et al [5] hypothesized this deviance to be a cognitive endophenotype. They compared 22 unaffected first-degree relatives of OCD patients as genetic risk carriers to 22 unmedicated OCD patients and 22 healthy controls without such family history.…”