April 2022

  • Zoom Brown Bag: Studying sensory reweighting via the perception of gravity in aging with central vision loss

    Zoom Brown Bag: Studying sensory reweighting via the perception of gravity in aging with central vision loss

    Event Date:

    Abstract: To interact with the world around us, we must accurately perceive our environment and how we are moving within it. For this, visual, vestibular, and somatosensory (proprioceptive and tactile) inputs must be integrated and appropriately (re)weighted depending on signal reliability and environmental and task demands. This sensory reweighting process is therefore dynamic. Age-related sensory deficits are thought to lead older adults to systematically up-weight visual information, however. This visual dependence in older age is associated with alterations in body coordination, adaptation difficulties, balance, and falls, among others, and such limitations can be debilitating when visual information is reduced and unreliable, as in the case of central visual field loss due to age-related macular degeneration (AMD). It is unclear whether aging allows for sensory adaptations to compensate for vision loss in AMD, and it is possible that visual dependence persists, whereby affected individuals are relying more on the sense that is failing them. We are therefore examining sensory reweighting in AMD with classic measures of subjective visual vertical estimation, an essential aspect of space perception and postural control. Prior to studying the complex case of AMD, where aging, vision loss, and an eccentric oculomotor reference frame may all play a part, we first examine whether the use of eccentric viewing strategies alone may affect verticality judgments. Since individuals with binocular central field loss commonly employ an eccentric preferred retinal locus (PRL) in their better eye, and given that eye position signals also contribute to individuals’ space perception and postural orientation and control, the consequences of AMD may extend beyond visual and oculomotor tasks. Thus, in addition to investigating the potential influence of eye eccentricity on verticality judgments in younger adults with no vision deficits, we look at individuals with monocular AMD who can serve as their own controls. Preliminary results seem to indicate that older adults with AMD rely on visual context in their subjective vertical estimation, despite their vision loss, and that eccentric viewing alters one's verticality perception. The potential interaction of eye orientation and contextual visual information will be essential to consider further in designing rehabilitation protocols for individuals with AMD. https://www.ski.org/users/catherine-agathos

    Improving Zoom accessibility for people with hearing impairments People with hearing impairments often use lipreading and speechreading to improve speech comprehension. This approach is helpful but only works if the speaker’s face and mouth are clearly visible. For the benefit of people with hearing impairments on Zoom calls, please enable your device’s camera whenever you are speaking on Zoom, and face the camera while you speak. (Feel free to disable your camera when you aren’t speaking.)

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  • Zoom Colloquium: The Angry Crowd Bias: Social, Cognitive, and Perceptual Mechanisms

    Zoom Colloquium: The Angry Crowd Bias: Social, Cognitive, and Perceptual Mechanisms

    Event Date:

    Abstract - Accuracy and bias may seem at odds in perception. Yet they are as much complementary as they are contradictory. For example, people are excellent at recognizing others’ expressions of emotion, but when faces are hard to see, people are biased to report that individuals look threatening, or angry. Error in name only, these sorts of negative biases may be protective or functional, and they can be found alongside countless examinations of accuracy in the vision and social cognition literatures. Yet little work in the field of ensemble coding has examined bias during perception of crowds. This is surprising because biases, especially negative biases, should manifest differently for judgments about many people seen at once, or in succession. Crowds exert different pressures on perceivers than do individuals, people behave differently when in crowds than they do when they’re alone, and people hold different beliefs about crowds than individuals. In this talk, I will share new findings demonstrating that bias to report anger is greatly amplified when people make judgments about crowds compared with individuals. Furthermore, perceivers are biased in the way they attend to faces in crowds, which leads them to estimate that crowds are more emotional than they actually are, especially when those crowds are angry. Finally, I will share plans for a new program of work (including drift-diffusion modeling, eye-tracking, and Generative Adversarial Networks) to examine how the identities of people in a crowd (e.g., race, gender, age, etc.) impact biased judgments of their emotion. https://alumni.du.edu/about/faculty-directory/timothy-daniel-sweeny

    Improving Zoom accessibility for people with hearing impairments People with hearing impairments often use lipreading and speechreading to improve speech comprehension. This approach is helpful but only works if the speaker’s face and mouth are clearly visible. For the benefit of people with hearing impairments on Zoom calls, please enable your device’s camera whenever you are speaking on Zoom, and face the camera while you speak. (Feel free to disable your camera when you aren’t speaking.)

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