Semantic Expectation Effects on Object Detection: Using Figure Assignment to Elucidate Mechanisms

Abstract

Recent evidence suggesting that object detection is improved following valid rather than invalid labels implies that semantics influence object detection. It is not clear, however, whether the results index object detection or feature detection. Further, because control conditions were absent and labels and objects were repeated multiple times, the mechanisms are unknown. We assessed object detection via figure assignment, whereby objects are segmented from backgrounds. Masked bipartite displays depicting a portion of a mono-oriented object (a familiar configuration) on one side of a central border were shown once only for 90 or 100 ms. Familiar configuration is a figural prior. Accurate detection was indexed by reports of an object on the familiar configuration side of the border. Compared to control experiments without labels, valid labels improved accuracy and reduced response times (RTs) more for upright than inverted objects (Studies 1 and 2). Invalid labels denoting different superordinate-level objects (DSC; Study 1) or same superordinate-level objects (SSC; Study 2) reduced accuracy for upright displays only. Orientation dependency indicates that effects are mediated by activated object representations rather than features which are invariant over orientation. Following invalid SSC labels (Study 2), accurate detection RTs were longer than control for both orientations, implicating conflict between semantic representations that had to be resolved before object detection. These results demonstrate that object detection is not just affected by semantics, it entails semantics.

Scene-selective brain regions respond to embedded objects of a scene

“…However, the results of the current study emphasize the integrative nature of object and scene understanding. The results provide support for the role of context in object perception (e.g., Cacciamani et al, 2014; Flowers et al, 2020; Quek & Peelen, n.d.; Skocypec & Peterson, 2022) and that scene processing inherently includes the processing of the associations embedded within it (Aminoff, 2014; Aminoff & Tarr, 2015, 2020).…”

Semantic Influences on Object Detection: Drift Diffusion Modeling Provides Insights Regarding Mechanism

“…In the present article, we use computational modeling to reveal the mechanisms whereby semantics influenced object detection in a recent experiment by Skocypec and Peterson (2022). We begin by discussing the “Label-Feedback” hypothesis, a leading hypothesis regarding how semantics might influence object detection that was supported by previous experiments in which stimuli were repeated multiple times.…”

“…In studies that provided support for the Label-Feedback hypothesis, a basic-level label (i.e., a label commonly paired with an object) was paired with a particular exemplar many times (e.g., Lupyan & Ward, 2013; Pinto et al, 2015; Stein & Peelen, 2015). However, with so much repetition, participants may have learned to respond accurately following a basic-level label when they detected low-level features rather than the object configuration which entails representations of the relationship among features (Gayet et al, 2014; Skocypec & Peterson, 2022). Thus, the use of repetition may produce a misunderstanding of how basic- level labels typically affect object detection.…”

“…Skocypec and Peterson (2022) assessed object detection via figure assignment reports regarding stimuli like those in Figure 1. In these stimuli, a portion of a well-known (i.e., “familiar”) object with a typical upright is depicted on one side of a central border that divides the display into two equal-area halves.…”

“…In their experiments, Skocypec and Peterson (2022) investigated the effect of word labels on object detection in these bipartite displays. Participants in experimental labels-present groups were presented with either a valid or an invalid label before being shown a brief, masked, exposure of a bipartite display depicting a portion of a familiar object in either an upright or an inverted orientation.…”