The pupil is best known for changing size in reaction to light. In a dark room, your pupils open wide to let in more light; as soon as you step outside into the sunlight, the pupils shrink to pinpricks. This keeps the retina at the back of the eye from being overwhelmed by bright light. Something similar happens in response to psychological stimuli, says Bruno Laeng of the University of Oslo, who cowrote the paper with Sylvain Sirois of Universit\u00e9 du Qu\u00e9bec \u00e0 Trois-Rivi\u00e8res and Gustaf Gredeb\u00e4ck of Uppsala University in Sweden. When someone sees something they want to pay closer attention to, the pupil enlarges.<\/strong> It\u2019s not clear why this happens, Laeng says. \u201cOne idea is that, by essentially enlarging the field of the visual input, it\u2019s beneficial to visual exploration,\u201d he says.<\/p>\n However it works, psychological scientists can use the fact that people\u2019s pupils widen when they see something they\u2019re interested in.<\/p>\n Laeng has used pupil size to study people who had damage to the hippocampus, which usually causes very severe amnesia. Normally, if you show one of these patients a series of pictures, then take a short break, then show them another series of pictures, they don\u2019t know which ones they\u2019ve seen before and which ones are new. But Laeng measured patients\u2019 pupils while they did this test and found that the patients did actually respond differently to the pictures they had seen before. \u201cIn a way, this is good news, because it shows that some of the brains of these patients, unknown to themselves, is actually capable of making the distinction,\u201d he says.<\/p>\n Pupil measurement might also be useful for studying babies. Tiny infants can\u2019t tell you what they\u2019re paying attention to. \u201cDevelopmental psychologists have used all kinds of methods to get this information without using language,\u201d Laeng says. Seeing what babies are interested in can give clues to what they\u2019re able to recognize\u2014different shapes or sounds, for example.\u00a0 A researcher might show a child two images side by side and see which one they look at for longer. Measuring the size of a baby\u2019s pupils could do the same without needing a comparison.<\/p>\n The technology already exists for measuring pupils\u2014many modern psychology studies use eye-tracking technology, for example, to see what a subject is looking at, and Laeng and his coauthors hope to convince other psychological scientists to use this method.<\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":" From the Association for Psychological Science press release: The eyes are the window into the soul\u2014or at least the mind, according to a new paper published in Perspectives on Psychological… Read more »<\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[4,6],"tags":[179,160,74,12,41],"_links":{"self":[{"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/posts\/964"}],"collection":[{"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/comments?post=964"}],"version-history":[{"count":2,"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/posts\/964\/revisions"}],"predecessor-version":[{"id":966,"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/posts\/964\/revisions\/966"}],"wp:attachment":[{"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/media?parent=964"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/categories?post=964"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/therapytoronto.ca\/news\/wp-json\/wp\/v2\/tags?post=964"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"\"](\"http:\/\/therapytoronto.ca\/images\/blogpics\/Eyes.jpg\" "\\"eyes\\"")
The eyes are the window into the soul\u2014or at least the mind, according to a new paper published in Perspectives on Psychological Science<\/em>, a journal of the Association for Psychological Science. Measuring the diameter of the pupil, the part of the eye that changes size to let in more light, can show what a person is paying attention to.<\/strong> Pupillometry, as it\u2019s called, has been used in social psychology, clinical psychology, humans, animals, children, infants\u2014and it should be used even more, the authors say.<\/p>\n