Early Visual Processing of Feature Saliency Tasks: A Review of Psychophysical Experiments

Abstract

The visual system is constantly bombarded with information originating from the outside world, but it is unable to process all the received information at any given time. In fact, the most salient parts of the visual scene are chosen to be processed involuntarily and immediately after the first glance along with endogenous signals in the brain. Vision scientists have shown that the early visual system, from retina to lateral geniculate nucleus (LGN) and then primary visual cortex, selectively processes the low-level features of the visual scene. Everything we perceive from the visual scene is based on these feature properties and their subsequent combination in higher visual areas. Different experiments have been designed to investigate the impact of these features on saliency and understand the relative visual mechanisms. In this paper, we review the psychophysical experiments which have been published in the last decades to indicate how the low-level salient features are processed in the early visual cortex and extract the most important and basic information of the visual scene. Important and open questions are discussed in this review as well and one might pursue these questions to investigate the impact of higher level features on saliency in complex scenes or natural images.

Encoding Pleasant and Unpleasant Expression of the Architectural Window Shapes: An ERP Study

“…Electroencephalogram (EEG) recording is commonly used in the clinic and research studies for diagnosing neurological disorders such as seizures, as well as measuring actual brain function. It has been shown that the architectural features of a visual scene significantly influence the perception, social behaviors and reactions of human observers to their environments (Delvin and Nasar, 1989; Madani Nejad, 2007; Kamkar et al, 2018), while their underlying neural mechanisms are less well understood (Vartanian et al, 2013; Papale et al, 2016). Therefore, a more detailed understanding of how the brain perceives and processes the features of building components is an interesting goal in neuro-architecture (Chauhan and Moulik, 2014).…”

Multiple-target tracking in human and machine vision

“…Results showed that subjects use a range of features to highlight target-distractor differences that facilitate tracking. Surface features such as color and shape are encoded in early visual-processing areas of the brain [58]. According to the preceding findings, these features undoubtedly influence the processing of targets and distractors during MTT and facilitate tracking.…”

A Saliency Aware CNN-Based 3D Model Simplification and Compression Framework for Remote Inspection of Heritage Sites

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