Justin Ostrofsky

Observational drawing biases are predicted by biases in perception: Empirical support of the misperception hypothesis of drawing accuracy with respect to two angle illusions

We tested the misperception hypothesis of drawing errors, which states that drawing accuracy is strongly influenced by the perceptual encoding of a to-be-drawn stimulus. We used a highly controlled experimental paradigm in which nonartist participants made perceptual judgements and drawings of angles under identical stimulus exposure conditions. Experiment 1 examined the isosceles/scalene triangle angle illusion; congruent patterns of bias in the perception and drawing tasks were found for 40 and 60° angles, but not for 20 or 80° angles, providing mixed support for the misperception hypothesis. Experiment 2 examined shape constancy effects with respect to reproductions of single acute or obtuse angles; congruent patterns of bias in the perception and drawing tasks were found across a range of angles from 29 to 151°, providing strong support for the misperception hypothesis. In both experiments, perceptual and drawing biases were positively correlated. These results are largely consistent with the misperception hypothesis, suggesting that inaccurate perceptual encoding of angles is an important reason that nonartists err in drawing angles from observation.

Perceptual Grouping in Artists and Non-Artists: A Psychophysical Comparison

Are advantages in complex object perception that have been observed in artists supported by advantages in more basic perceptual processes? To address this question, we compared artists and non-artists on a psychophysical task measuring perceptual grouping thresholds in order to test for group differences in sensitivity to perceptual grouping cues. Participants viewed grids of dots that could be perceptually grouped into a series of lines. The level of organization of stimuli was progressively reduced until perceived grouping was ambiguous. While artists were not observed to have an overall advantage relative to non-artists, non-artists exhibited sex differences in perceptual grouping sensitivity that artists did not. This suggests that the visual systems of male and female artists may be less differentiated than non-artist males and females.

Face Inversion Impairs the Ability to Draw Long-Range, but Not Short-Range, Spatial Relationships Between Features

Art instructors have promoted the idea that reproducing upside-down models facilitates drawing accuracy. However, perceptual research has demonstrated that face inversion impairs the perception of long-range and, to a lesser extent, short-range spatial relationships between features. This suggests that drawing an upside-down face model might impair, rather than facilitate, drawing performance with respect to the accuracy of depicting the spatial relationships between features. In this study, participants drew an upright and upside-down face. Participants were less accurate in drawing the long-range spatial relationship between the eyes and mouth when drawing the upside-down face than when drawing the upright face. In contrast, they were equally accurate in drawing the short-range spatial relationships between the (a) eyes and eyebrows, (b) nose and mouth, and (c) two eyes when drawing the upright and upside-down models. This result fails to empirically validate the effectiveness of drawing models upside-down for the purposes of facilitating drawing accuracy.

Developmental and Geographic Analyses of Spatial Biases in Face Drawings Produced by Children

A recent study of a large sample of children living in London demonstrated that their imagination-based self-portraits exhibited systematic drawing biases such as depicting the head too round and the eyes too far up the head. The present study aimed to replicate and extend on these findings in a sample of self-portraits produced by children from all around the world to determine if these drawing biases are universal or culturally specific to children living in Western Europe. Developmentally, children ranging in age from 3 to 11 years old were observed to draw the head too round and the eyes too high up the head. Children ranging in age from 3 to 8 years old, but not children ranging in age from 9 to 11 years old, were observed to draw the mouth too high up the head. As the children grew in age from 3 to 11 years old, these biases persisted, but there were linear trends for the biases of drawing the eyes and mouth too high up the head to become less exaggerated with increasing age. Geographically, children living in Africa, Asia, Europe, and South/Central America were all observed to exhibit these three systematic biases, indicating that these are universal drawing biases not affected by the geographic location the children were raised in.

The effect of object interpretation on the appearance of drawings of ambiguous figures.

We studied how the appearance of observational drawings is affected by how individuals interpret the model object they are copying. Participants were asked to draw 2 ambiguous figure models (Fisher’s Gypsy/Girl with Mirror and Man/Girl figures). Before being exposed to the models, participants were randomly assigned to receive 1 of the 2 possible interpretations of the figures during the task instructions. After all the drawings were completed, a group of independent judges rated the appearance of the drawings with respect to what object they thought the drawing was trying to depict. Analysis of the ratings indicated that the ambiguous figure interpretations provided to participants during the task instructions affected the ultimate appearance of their drawings. For the most part, participants’ drawings were biased to appear more like the object that was the subject of the interpretation they received during the task instructions than the alternative possible interpretation they did not receive. These results demonstrate that the categorization of model objects affects the ultimate appearance of drawings of that model. This supports the general perspective that top-down processes affect observational drawings beyond the bottom-up encoding of the visual information inherent in a model. The possible mechanisms producing this effect are discussed.

The Relationship Between Need for Cognitive Closure and the Appreciation, Understanding, and Viewing Times of Realistic and Nonrealistic Figurative Paintings

We assessed the relationship between Need for Cognitive Closure (NFC) personalities and appreciation, comprehension, and viewing time for realistic paintings depicting objects/scenes and nonrealistic paintings that ambiguously depict objects/scenes. For both types of paintings, liking was positively correlated with degree of understanding. Realistic paintings were better understood, liked, and evaluated for less time than nonrealistic paintings. High and low NFC participants were equal in their liking and comprehension of realistic paintings. However, low NFC participants understood and liked nonrealistic paintings more than high NFC participants. High NFC participants also exhibited an urgency tendency, indicated by their shorter viewing times for both types of paintings as compared with low NFC. We suggest that high NFC is associated with intolerance of and lower appreciation for ambiguous, nonrealistic paintings. This may be due to unwillingness to spend sufficient viewing time to achieve the level of understanding needed to appreciate ambiguous art.