Rapidly estimating numerosity independent of size-related distance or occlusion

Riesen, Guillaume; Ruda, Harald; Mingolla, Ennio

doi:10.1167/14.10.879

Cited by 1 publication

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Because of both these visual constraints in 3-D world perception and the intrinsic structure of the eyes, the number and extent of visible fragmented surfaces impressed on the retina, cannot directly convey the number of objects in the external world (cf. Riesen et al, 2014). For example, in a preliminary computational and psycho-physical study with naturalistic 3-D models (e.g., trees of apples), it has been shown that performance in a simple comparison task was unaffected by the extent of visible object surface (e.g., apples) because the judgments were robust to variations in object occlusion or visual angle (Riesen et al, 2014).…”

Section: Discussionmentioning

confidence: 99%

“…Riesen et al, 2014). For example, in a preliminary computational and psycho-physical study with naturalistic 3-D models (e.g., trees of apples), it has been shown that performance in a simple comparison task was unaffected by the extent of visible object surface (e.g., apples) because the judgments were robust to variations in object occlusion or visual angle (Riesen et al, 2014). The authors reasoned that if the visible surface actually encoded the numerosity magnitude, then increasing the object occlusion (or reducing the visible surface) of the stimuli should have produced a numerosity underestimation (Riesen et al, 2014).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Visual illusions as a tool to hijack numerical perception: Disentangling nonsymbolic number from its continuous visual properties.

Adriano

Rinaldi²,

Girelli

2021

Journal of Experimental Psychology: Human Perception and Perfor

View full text Add to dashboard Cite

The past few years have witnessed a fervent theoretical debate about the exact visual mechanisms supporting nonsymbolic number processing. The idea that quantity information is extracted through a primitive visual segmentation algorithm has been challenged by recent models, which rather tap on low-level features confounded with numerosity (i.e., density, convex hull, or total area). Here we used an original manipulation based on visual illusions to disentangle whether visual numerosity processing operates over discrete units or rather over continuous variables. In particular, we generated a set of stimuli composed by open inducers (e.g., like a pac-man shape) that simulate physical connections with Kanizsa-like illusory contours (ICs). Test sets contained pairs of collinear open inducers items that prompted 0 IC, 2 IC, or 4 IC lines connecting 2 objects. Critically, low-level visual features were fully controlled across connectedness levels. We found a systematic underestimation as we increased the IC connections when participants had to select the larger between 2 sets of objects (Experiment 1) but not in the case of aligned closed inducers preventing illusory lines (Experiments 2A and 2B). We also found a systematic numerosity underestimation when both IC connections and continuous features (e.g., convex hull) were independently manipulated in test stimuli (Experiment 3). Finally, these results were shown to be task independent because the same effects of IC connections were replicated in an estimation task (Experiment 4). Taken together, our findings indicate that numerosity perception relies on basic visual-segmentation mechanisms, pointing out the need of new theoretical frameworks integrating both continuous and discrete perceptual number signals.

show abstract

Section: Discussionmentioning

confidence: 99%