Eye Movement Dysfunction as a Biological Marker of Risk for Schizophrenia

Abstract

Evidence for the specificity of SPEM dysfunction to diagnosed schizophrenia, as well as to healthy individuals with a genetic vulnerability to schizophrenia, suggests that the SPEM task has efficacy as a test of gene carrier status in schizophrenia, and therefore as a trait marker of risk for schizophrenia. Future studies should seek to explore the relationships between SPEM and other eye movement dysfunctions (antisaccades, express saccades), in view of evidence that some of these dysfunctions also show specificity for schizophrenia.

Evidence for a role of nicotinic acetylcholine receptors in schizophrenia

“…Sensory processing deficits are common among schizophrenia patients and are poorly treated by typical antipsychotics, although some atypical antipsychotics have proven to be more efficacious. Deficits in sensory processing are quantifiable with several different paradigms, including prepulse startle inhibition (PPI) (for review see (74-77), smooth pursuit eye movements (SPEM) (for review see (78)(79)(80) and P50 sensory inhibition. In P50 sensory inhibition, repeated stimuli induce activity in an inhibitory circuit in normal individuals such that the evoked response to the repetitive information is suppressed (81)(82)(83)(84)(85)(86).…”

Oculomotor activity as an indicator of disturbances in perception and programming in patients with schizotypal disorder

“…Такие саккады многими исследователями [26] называются интрузивными и увеличивают погрешность между положением глаз и наблюдаемой целью. Понятие микро-или экспресс-саккад (саккады с очень короткой длительностью) является родственным и также ранее неоднократно обнаруживалось у больных шизофренией [9,10,27].…”

“…Так, A. Sereno и P. Holzman [9] обнаружили, что больные шизофренией по частоте встречаемости экспресс-саккад отличаются от пациентов с биполярным расстройством, а наличие этих кратковременных саккад в присутствии точки фиксации, по данным K. Lee и соавт. [10], отличает их от пациентов с лобным синдромом.…”

“…Высокая частота коротких непроизвольных саккад отражает повышенную отвлекаемость таких больных на несущественную информацию и свидетельствует об ослабленном тормозном механизме в системе фиксации и процессах визуального восприятия [10,11]. Неоднократно отмечалась недостаточная избирательность больных шизофренией или шизотипическим расстройством, при которой нерелевантные стимулы обрабатываются ими в той же степени интенсивно, как и релевантные [11].…”

Qualitative and quantitative aspects of information processing in first psychosis: Latent class analyses in patients, at‐risk subjects, and controls

“…Abnormalities in earlier ERP components, including P50 and N100, may already be present in first‐hospitalized patients but are most prominent in chronic schizophrenia patients (Brockhaus‐Dumke et al., ) and correlate with clinical symptoms (Boutros et al., ). With regard to the eye movement tasks, both pursuit and antisaccade performance were shown to be stable over time in schizophrenia (Gooding, Mohapatra, & Shea, ; O'Driscoll & Callahan, ; Turetsky et al., ), although associations of SPEM performance with symptomatology, in particular disorganization symptoms, have been reported (Lee & Williams, ). Importantly, these studies have investigated state and trait aspects of neurophysiological impairments in patients diagnosed with schizophrenia without inclusion of the prodromal period.…”