Evaluating the human ongoing visual search performance by eye tracking application and sequencing tests

• Published in: Computer methods and programs in biomedicine Vol. 107; no. 3; pp. 468 - 477
• Main Authors: Veneri, Giacomo, Pretegiani, Elena, Rosini, Francesca, Federighi, Pamela, Federico, Antonio, Rufa, Alessandra
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ireland Ltd 01.09.2012; Elsevier
• Subjects: Adult; Algorithms; Attention; Biological and medical sciences; Computers; Data Interpretation, Statistical; Eye Movements; Female; Fixation, Ocular; Fixations; Humans; Internal Medicine; Male; Medical sciences; Models, Theoretical; Neuropsychological Tests; Other; Pattern Recognition, Visual; Photic Stimulation - methods; Psychomotor Performance; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Reaction Time; Saccade planning; Saccades - physiology; Signal Processing, Computer-Assisted; Spatial visual search; Technology. Biomaterials. Equipments. Material. Instrumentation; Time Factors; Trail making test; Vision, Ocular; Visual Perception - physiology; Saccade planning; Spatial visual search; Fixations; Trail making test; Biomedical engineering
• ISSN: 0169-2607; 1872-7565
• DOI: 10.1016/j.cmpb.2011.02.006

Abstract Human visual search is an everyday activity that enables humans to explore the real world. Given the visual input, during a visual search, it is necessary to select some aspects of input to shift the gaze to next target. The aim of the study is to develop a mathematical method able to evaluate the visual selection process during the execution of a high cognitively demanding task such as the trial making test part B (TMT). The TMT is a neuro-psychological instrument where numbers and letters should be connected to each other in numeric and alphabetic order. We adapted the TMT to an eye-tracking version, and we used a vector model, the “eight pointed star” (8PS), to discover how selection (fixations) guides next exploration (saccades) and how human top-down factors interact with bottom-up saliency. The results reported a trend to move away from the last fixations correlated to the number of distracters and the execution performance.