“Fundamentally Misunderstanding Visual Perception: Adults’ Belief in Visual Emissions”, 2002-06-01 (; backlinks; similar):
[cf. typical mind] The authors reviewed research about a profound folk psychology misconception that is present among college students, namely, the belief that the process of vision includes emanations from the eyes, an idea that is consistent with the extramission theory of perception, which was originally professed by early Greek philosophers and which persisted in scholarly circles for centuries. The authors document the strength and breadth of this phenomenon and the abject failure of traditional educational techniques to overcome this belief, and they reveal that students are leaving psychology courses with a flawed understanding of one of the most studied processes in the history of psychology-visual perception. Some suggestions are offered for overcoming this misconception in traditional college classroom settings.
…Piaget ([The child’s conception of the world] 1929/196757ya), however, was perhaps the first to note an odd type of misunderstanding that children have about vision. He commented on a report of a child who stated that looks can mix when they meet, and, along with other observations, Piaget suggested that children believe in emissions from the eyes during vision. In an apparently unpublished work, Piaget (referenced in 1971/1974 [Understanding Causality]) claimed to have found strong evidence of extramission beliefs in children
…We examined the responses of children and adults to questions asking whether there was visual input and/or output during the act of perception (eg. 1994; see 1996a, for a review of several studies). This research revealed widespread evidence of extramission beliefs among children, with a decline in such beliefs over age. We were, however, startled to find that, despite consistent developmental trends toward decreasing extramission beliefs with age, large numbers of adults also affirmed a belief in visual extramissions. Apparently some college students were behaving like prescientific ancient philosophers in affirming an extramission understanding of vision that is entirely at odds with the theories of modern science.
Perhaps even more disturbing to us was the strong likelihood that this misconception existed despite our participants’ having received formal education on the topics of sensation and perception. For example, we typically found extramission beliefs among college students who were tested after they had received instruction on sensation and perception in introductory psychology classes, thus suggesting not only that adults were affirming extramission beliefs but that such beliefs were resistant to education. We were confronted, then, with the likelihood that students were emerging from basic-level psychology courses without an understanding of one of the most important psychological processes, namely, visual perception.
…On such intromission-extramission (i-e) tests, large numbers of adults gave extramission responses, with the percentages varying depending on the particular representations of vision shown on the screen. For example, in one study ( et al 1996), when given a simple choice between input versus output, ~13% of the adults selected output only. When available, however, the favored extramission choices were representations that showed (a) simultaneous input and output and (b) input followed by output. On trials that included these favorite choices, the percentage of extramission responses ranged 41%–67% (the greater the number of preferred choices offered, the greater the frequency of extramission responses). Data presented later in this article ( et al 2001) likewise show more than 50% of adults giving extramission responses…In all of these cases, we found convincing evidence for extramission beliefs. For example, when students were asked to draw and number arrows to show how a person sees a balloon, 86% showed some evidence of extramission (ie. outward arrows), whereas when adults were repeatedly asked specifically to draw whether something comes into or goes out of the eyes when a person sees a balloon, 69% placed outward-pointing arrows in their drawings.
…Whatever the test, we have consistently found substantial numbers of college students reporting extramission beliefs.
We have also varied the visual referent in our questions, with disturbing findings. In one non-computer test, we asked students about vision when presenting them with different visual referents, namely a shining light bulb, the same bulb unlit, and a white Styrofoam ball the same size as the unlit bulb ( et al 1996). We expected that referring to the lit bulb would diminish extramission responses—indeed, that it would be nearly impossible to maintain extramission beliefs in reference to light shining in one’s face. We also assumed that initial intromission responses, encouraged by reference to the shining light bulb, would generalize. That is, we expected positive transfer from questions about the shining light bulb to subsequent questions about the non-luminous objects.
The results supported the idea that asking i-e questions about a shining light would cause a decrease in extramission responses. But asking about the lit bulb did not even come close to eliminating extramission beliefs: 33% of the adults tested affirmed extramission in reference to viewing the lit bulb. Moreover, there was no sign of positive transfer from questions about the lit bulb to questions about the non-luminous objects. In fact, the opposite occurred. When we switched from the lit bulb to the non-luminous objects, there was an increase in extramission responses, as if turning off the light signaled that there were no more incoming rays.
…we have routinely asked questions about the necessity of extramissions for vision. For example, we have asked whether a person can see if nothing leaves the eye and whether what exits the eye helps people see. In one study, at least 70% of adult participants who reported extramission beliefs on the last question of the test stated on one of the probe questions that they believed visual extramissions were functional in vision. Second, we have directly tested for the possibility that extramission interpretations were due to participants misinterpreting i-e questions. In his master’s thesis, 1996 [“Effects of considerations of necessity and scientific reasoning upon beliefs about visual perception”] gave college students intensive training on the concept of necessity, before asking them specifically whether it was necessary that something leave the eye during the act of vision. The training had no effect on responses to i-e questions. In fact, many participants who affirmed on a pretest question that something exiting the nose was not necessary for olfaction went on to claim that visual extramissions were necessary for seeing.
…The fact that the learning effects for both college students and 8th graders disappeared [in et al 2001] was striking. Consider, for example, the performance of the college students, who were presumably the most cognitively advanced. On the first posttest, 100% of the students in the refutational group had 5 or more of 8 items correct, compared with 54% in the simplified-explanation group and 29% in the control group. On the delayed test, 7 of the 17 college students who returned for testing in the refutational-teaching group had fewer than 5 of the 8 items correct.
Recall that no student in this group had fewer than 5 items correct at Time 1. Moreover, of the 7 whose performance declined, 6 had had perfect scores at Time 1. The long-term ineffectiveness of the training for the college students is further revealed by the fact that 53% of the participants in the 2 experimental groups at that grade level had 4 or fewer correct responses.
…A related strategy is to foster logical or cognitive dissonance. In one pilot study, for example, when we were trying to explore the breadth of the extramission misunderstanding, one participant tenaciously defended his extramission beliefs until we asked him whether someone would be able to see the image coming from his eyes, at which point he acknowledged, rather sheepishly, that nothing has to leave the eyes in order for people to see.