Objective: In this study, we aimed to investigate whether there is a fast decay in the iconic memory of patients with Obsessive Compulsive Disorder (OCD) compared to healthy individuals by taking into consideration the clinical OCD subtypes.
Method: The study included 74 patients diagnosed with OCD on the basis of the DSM 5 criteria and 63 healthy individuals. The OCD patients were grouped as washers, checkers, both washers and checkers, and non-washers and non-checkers. All participants took a partial report test (PRT) to compare iconic memory performance between the healthy control group and the OCD group as a whole and in OCD subgroups.
Results: Loss of iconic memory did not differ between OCD group and the controls. The iconic memory scores, expressed as the d' values, at specified time points correlated negatively with age and positively with education duration in all groups. When the subgroup data were analyzed by controlling for age, the d1'value showing formation of iconic information was lower in the washers subgroup in comparison to the checkers subgroup and the nonwashers and non-checkers subgroup. The d7' value was also lower in the washers subgroup than in the the non-washers and non-checkers subgroup and the healthy control group. The iconic decay rate of the washers subgroup between the time points d6' and d7' was significantly higher in comparison to the healthy control group. The scores of OCD patients on the washing subscale of the Maudsley Obsessive Compulsive Inventory (MOCI) showed negative correlations with the iconic memory scores at all time points.
Conclusion: This study showed that washer OCD patients may have impaired iconic formation and fast iconic decay, which could significantly affect the amount of information transferred to visual memory.