Date Presented 03/27/20
This study carried out a performance-based task combined with an eye-tracker device for both a control group and a group of people coping with severe mental illnesses. This was done in order to better understand difficulties in task performance and to deepen OTs’ and cognitive scientists’ understanding of client factor and to identify interventions in the most favorable way for the individual. Preliminary results show a difference between the groups in both observational and objective findings.
Primary Author and Speaker: Sivan Regev
Contributing Authors: Naomi Josman, Avi Mendelsohn
PURPOSE: Individuals coping with severe mental illnesses (SMI) experience difficulties in performing instrumental activities of daily living that require intact executive functions (Josman & Regev, 2018), a primary example being grocery shopping. Previous studies in SMI individuals have operated behavioral and physiological impairments in laboratory models, or used performance-based tasks in an observational approach. In our study we aim to use a translational research approach by carrying out a performance-based naturalistic task combined with cognitive science methods in SMI and control groups in order to distinguish the differences in task performance.
DESIGN: This quasi-experimental study took place in a daily activity that enabled the examination of efficiently performing a complex task in a naturalistic environment. Eligibility criteria required participants to receive public services that demand meeting the Israeli standard for “psychiatric disability”, severe enough to compromise at least 40% of their functioning. This, determined by a medical committee including a psychiatrist, and recognized by Israeli national insurance regulations. Individuals for the SMI group were recruited through the public services, whereas an age- and gender-matched control group was recruited for comparison.
METHOD: Eighteen participants, nine meeting the SMI criteria and nine matched controls, performed the Test of Grocery Shopping Skills (TOGSS; Hamera and Brown, 2000), which is a performance-based test that assesses an independent living skill of grocery shopping in both a local and an unfamiliar supermarket. Participants were required to search and find ten predefined items of specific sizes at the most economical price, and to do so in an efficient manner. The test measures three indices, namely accuracy, efficiency and strategy use. Participants performed the test while wearing an eye-tracking device, which measured and recorded the location and duration of fixations throughout. The acquired data was subsequently analyzed using designated software (BeGaze). Events were manually analyzed for each item selection by consistent criterions. The amount and duration of fixations were computed separately for sixteen predefined areas of interest (AOI) within each event location (e.g. price ticket, target item, irrelevant items, etc.). Wilcoxon signed-rank tests were used to compare both TOGSS and eye-tracker indices between groups.
RESULTS: Duration of the TOGSS was significantly higher for the research group compared to matched controls (P<0.05), while accuracy and redundancy was not significantly different between the groups. For the analyzed events, fixation duration and glances count were found to be significantly different for one selection event (spaghetti bag) and not significant for the other (corn can), raising the importance of specific task structure as a component of the task analysis.
CONCLUSION: The findings from this study highlight how information is attended to by people with and without SMI, and how the cues given from the environment might affect the process of selection by the SMI population. This collaboration enables occupational therapists together with cognitive scientists to deepen their understanding regarding client factor and identify individual-tailored interventions.
References
Josman, N. & Regev, S. Dynamic Interactional Model in severe mental illness, metacognitive and strategy- based intervention. In N. Katz. & J. Toglia (Eds.). Cognition, Occupation and Participation across the life span Neuroscience, Neurorehabilitation, and Models of Intervention in Occupational Therapy. Bethesda: American Occupational Therapy Association. 387-403.
Hamera, E., & Brown, C. E. (2000). Developing a context-based performance measure for persons with schizophrenia: the test of grocery shopping skills. The American Journal of Occupational Therapy, 54(1), 20-25.
