Comparable search efficiency for human and animal targets in the context of natural scenes

Abstract

In a previous series of studies, we have shown that search for human targets in the context of natural scenes is more efficient than search for mechanical targets. Here we asked whether this search advantage extends to other categories of biological objects. We used videos of natural scenes to directly contrast search efficiency for animal and human targets among biological or nonbiological distractors. In visual search arrays consisting of two, four, six, or eight videos, observers searched for animal targets among machine distractors, and vice versa (Exp. 1). Another group searched for animal targets among human distractors, and vice versa (Exp. 2). We measured search slope as a proxy for search efficiency, and complemented the slope with eye movement measurements (fixation duration on the target, as well as the proportion of first fixations landing on the target). In both experiments, we observed no differences in search slopes or proportions of first fixations between any of the target-distractor category pairs. With respect to fixation durations, we found shorter on-target fixations only for animal targets as compared to machine targets (Exp. 1). In summary, we did not find that the search advantage for human targets over mechanical targets extends to other biological objects. We also found no search advantage for detecting humans as compared to other biological objects. Overall, our pattern of findings suggests that search efficiency in natural scenes, as elsewhere, depends crucially on the specific targetdistractor categories.

Bird expertise does not increase motion sensitivity to bird flight motion

“…This is consistent with work showing that the inversion effect in humans, at least when making judgments of the direction of human and animal terrestrial movement, can be explained predominantly by the local motion of the feet ( Troje & Westhoff, 2006 ), that is, a motion pattern not specific to humans. Again, in line with these studies using PL displays, although human targets are found more efficiently in natural scenes relative to machine targets ( Mayer et al, 2015 , 2017 ), human targets are not found more efficiently than terrestrial animal targets ( Mayer et al, 2020 ). Thus, although perceptual learning throughout a person's individual experience can influence detection of articulatory movement, the human brain is likely to come prepackaged with circuitry that enables rapid detection of terrestrial movement.…”

“…Fourth, there may also be limitations in creating PL videos of bird flight (e.g., occlusions). Future work can also use natural videos as used for human, terrestrial-animal, and mechanical motion ( Mayer et al, 2015 , 2017 , 2020 ). Thus, while the current study suggest that naturalistic exposure is not necessarily sufficient for developing domain-specific motion sensitivity, future work will need to further address under what circumstances it does or does not develop.…”

Bird expertise does not increase motion sensitivity to bird flight motion

“…This is consistent with work showing that the inversion effect in humans, at least when making judgements of the direction of human and animal terrestrial movement, can be explained predominantly by the local motion of the feet (Troje & Westhoff, 2006), that is, a motion pattern not specific to humans. Again, in line with these studies using PL displays, although human targets are found more efficiently in natural scenes relative to machine targets (Mayer et al, 2015(Mayer et al, , 2017, human targets are not found more efficiently than terrestrial animal targets (Mayer et al, 2020). Thus, although perceptual learning throughout a person's individual experience can influence detection of articulatory movement, the human brain is likely to come prepackaged with circuitry that enables rapid detection of terrestrial movement.…”

“…Future work can also use natural videos as used for human, terrestrial-animal and mechanical motion (Mayer et al, 2015(Mayer et al, , 2017(Mayer et al, , 2020. Thus, while the current study suggest that naturalistic exposure is not necessarily sufficient for developing domain-specific motion sensitivity, future work will need to further address under what circumstances it does or does not develop.…”

Look up to the body: An eye-tracking investigation of 7-months-old infants’ visual exploration of emotional body expressions

“…Methodological approaches that include the analysis of visual saliency and other low-level visual features will be particularly informative in this respect (Amso et al, 2014;Frank et al, 2009;Itti et al, 1998;Itti & Koch, 2001;Kibbe et al, 2018;Kwon et al, 2016;Mayer et al, 2015Mayer et al, , 2017Mayer et al, , 2020van Renswoude et al, 2019;Veale et al, 2017). The processing of low-level features can be affected by top-down feedback (e.g., Garrido-Vásquez et al, 2018;Hochstein & Ahissar, 2002), which means that for different perceptual tasks the same low-level features could contribute differently to participants' performance.…”