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Peterson, M. A.

Publications and source records attributed to Peterson, M. A..

3 recordsLinked to original sources

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

AbstractResearch shows that semantics, activated by words, impacts object detection. Skocypec & Peterson (2022) indexed object detection via correct reports of where figures lie in bipartite displays depicting familiar objects on one side of a border. They reported 2 studies with intermixed Valid and Invalid labels shown before test displays and a third, control, study. Valid labels denoted display objects. Invalid labels denoted unrelated objects in a different or the same superordinate-level category in studies 1 & 2, respectively. We used drift diffusion modeling (DDM) to elucidate the mechanisms of their results. DDM revealed that, following Valid labels, drift rate toward the correct decision increased, i.e., SNR increased. Following Invalid labels, SNR was lower only for upright displays in study 2. Thresholds were higher in studies 1 & 2 than in control. That more evidence must be accumulated from displays that follow labels implies that familiar object detection entails semantic activation. Threshold was even higher following Invalid labels in study 2, suggesting that more evidence from the display is needed to resolve within- category conflicts. These results support the view that semantic networks are engaged in object detection.

neuroscience↗

Normative Data for an Expanded Set of Stimuli for Testing High-Level Influences on Object Perception: OMEFA-II

We present normative data for bipartite displays used to investigate high-level contributions to object perception in general and to figure-ground perception in particular. In these vertically-elongated displays, two equal-area regions of different luminance abut a central, articulated, vertical border. In Intact displays, a portion of a mono-oriented well-known (\"familiar\") object is sketched along one side of the border; henceforth the \"critical side.\" The other side is the \"complementary side.\" We measured inter-subject agreement among 32 participants regarding objects depicted on the critical and complementary sides of the borders of Intact displays and two other types of displays: upright and inverted Part-Rearranged displays. The parts on the critical side of the border are the same in upright Intact and Part-Rearranged displays but spatially rearranged into a new configuration in the latter. Inter-subject agreement is taken to index the extent to which a side activates traces of previously seen objects near the central border. We report normative data for 288 regions near the central borders of 144 displays (48/type) and a thorough description of the image features. This set of stimuli is larger than an older \"Object Memory Effects on Figure Assignment\" (OMEFA) set. This new OMEFA-II set of high-resolution displays is available online (https://osf.io/j9kz2/).

neuroscience↗

Prior Experience Alters the Appearance of Blurry Object Borders

Object memories activated by borders serve as priors for figure assignment: figures are more likely to be perceived on the side of a border where a well-known object is sketched. Do object memories also affect the appearance of object borders? Memories represent past experience with objects; memories of well-known objects include many with sharp borders because they are often fixated. We investigated whether object memories affect appearance by testing whether blurry borders appear sharper when they are contours of well-known objects versus matched novel objects. Participants viewed blurry versions of one familiar and one novel stimulus simultaneously for 180ms; then made comparative (Exp. 1) or equality judgments regarding perceived blur (Exps. 2-4). For equivalent levels of blur, the borders of well-known objects appeared sharper than those of novel objects. These results extend evidence for the influence of past experience to object appearance, consistent with dynamic interactive models of perception.

animal behavior and cognition↗