SPATIAL WORKING MEMORY IN PRODROMAL STAGE: AN EYE TRACKING STUDY

Abstract

AbstractBackgroundIndividuals at ultra‐high risk for psychosis and bipolar disorder (UHR‐P and UHR‐BD) have shown cognitive abnormalities and sub‐threshold clinical features (de Paula et al., 2015; Metzler et al., 2014). Assessing saccadic eye movements is one of the useful methods for investigating high cognitive functions like spatial working memory and inhibition (Pierrot‐Deseilligny et al., 2005; Winograd‐Gurvich et al., 2008). Memory‐guided saccade (MGS) may be described as short‐term maintenance of attention both when a peripheral target is presented, and a delay screen. The purpose of this study was to examine the differences between clinical risk groups and healthy controls (HCs) based on the memory‐guided saccade.MethodThe study was included 33 UHR‐P (age: 21.61 ± 3.24), 28 UHR‐BD (age: 21.64 ± 4.02), and 28 HCs (age: 22.11 ± 4.03). Participants were selected from cases of clinical‐high‐risk criteria in interviews made with The Structured Interview of Psychosis Risk Syndromes and Bipolar Prodrome Symptom Interview and Scale. The memory‐guided saccade was measured with the number of the correct, incorrect, anticipatory and express saccades, also latency, peak velocity and amplitude for the correct saccades. Eye movement data were recorded from the right eye using an EyeLink 1000 Plus eye‐tracker. All results were analyzed with SPSS software.ResultThe anticipatory and express saccades in the cue screen, the anticipatory saccade in the delay screen and the total error response were significant between groups (p<0.05). There was a significant increase in UHR‐BD compared to controls in the error responses (p = 0.018). The anticipatory saccades in UHR‐BD were higher than in both UHR‐P and HC on the cue screen (p = 0.005 and p = 0.014), and controls on the delay screen (p = 0.027). In addition, the express saccades in the cue screen showed statistical differences between the risk groups (p = 0.032). ConclusionMemory‐guided saccades are used to assess the top‐down mechanism, including perceptual organization and goal‐directed behaviors, and are related to frontal lobe functions like spatial working memory and inhibitory control (Ostendorf et al., 2004). The elevation of incorrect saccades and predictive parameters like anticipatory saccades have indicated that individuals at the prodromal stage may appear spatial problems in inhibitory and exhibitory functions.