background : the ifa test is one of the most usual methods for detecting anti- toxoplasma antibod­ies, although it has not any unique standardization. it seems that the microscopic judg­ment of results is an important confounder in ifa test. therefore, we conducted the present study to clarify the role of microscopic observer, and other confounders on the test. methods: eighty sera were collect...

Model observers play an important role in the optimization and assessment of imaging devices. In this review paper, we first discuss the basic concepts of model observers, which include the mathematical foundations and psychophysical considerations in designing both optimal observers for optimizing imaging systems and anthropomorphic observers for modeling human observers. Second, we survey a f...

Despite rapid oscillations of the eyes, visual acuity is close to normal in many observers with congenital nystagmus (CN). This study investigated whether binocular hyperacuity thresholds are also close to normal in observers with CN. To do so, we assessed stereothresholds for horizontally and vertically separated line targets in three normal observers and six observers with idiopathic horizont...