Browsing by Subject "illusion"

Now showing 1 - 2 of 2
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    Making Sense of Hallucination
    (2019-10) Swanson, Link
    It can seem as if philosophy of perception has discussed hallucination almost more than perception itself. What is the difference between perception and hallucination? I argue that the concepts we normally associate with the term ‘hallucination’ are more useful for understanding what perception is than the concepts we normally associate with the term ‘perception’. Instead of claiming, as most theories do, that hallucination is a special type of (failed) perception, I instead argue that perception is a special type of (successful) hallucination. I introduce a concept called ‘S-hallucination’ and argue that it more accurately describes the process that we normally call perception. I defend this concept and situate it within classic debates in philosophy of perception.
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    Psychedelic Vision
    (2022-10) Swanson, Link
    The visual effects of psychedelic drugs are well-known but not well understood. In this dissertation, I investigate psychedelic visual phenomenology. I provide evidence and analysis to argue that psychedelics selectively impact contextual modulation at multiple levels of mental function. I report preliminary results of two experiments from a pilot study, in which we measured contrast surround suppression in humans under the psychedelic drug psilocybin, using psychophysical and EEG event-related potential (ERP) methods. We found that psilocybin enhanced perceptual surround suppression, and strengthened surround suppression of neural responses, compared with placebo. The results support the hypothesis that psychedelics enhance contextual modulation in visual processes, which has theoretical as well as practical implications for psychedelic therapy, cognitive neuroscience, and philosophy.