https:\/\/zoom.us\/j\/96047419957?pwd=bWdjVDRjMisyVFZmTVYvbExnVHo3UT09<\/a><\/p>\nMeeting ID: 960 4741 9957 (Passcode: 896970)<\/p>\n
<\/p>\n
Abstract: Visual masking has been used as an investigative tool to understand the dynamics of sensory and perceptual processing. Given that masking can also cause aware and<\/p>\n
unaware visual conditions, it has also found applications in visual awareness studies. Metacontrast is a common type of visual masking in which the target visibility is suppressed<\/p>\n
by presenting a following and spatially adjacent mask. However, the neural correlates of this common masking type are still open to discussion. Accordingly, the current thesis examined<\/p>\n
the influences of mask-to-target (M\/T) contrast ratio on metacontrast masking using electroencephalography (EEG). A contour discrimination task was employed to assess target<\/p>\n
visibility under different M\/T contrast ratios and stimulus onset asynchronies (SOAs). The behavioral results indicated U-shaped masking functions with strong target visibility<\/p>\n
suppression at intermediate SOA values for both low and high contrast ratios. Importantly, the contrast ratio significantly altered the suppression amount (i.e., the amount of masking effect)<\/p>\n
at these SOAs. Relying on these modulations, we analyzed EEG data and focused on VAN (visual awareness negativity, around 140-200 ms and 200-300 ms) and LP (late positivity,<\/p>\n
around 300-550 ms) components. In the VAN component range of 200-300 ms, we found an SOA dependency in evoked potentials. For all the component time ranges, the contrast ratio<\/p>\n
did not reveal significant alterations in evoked potentials. Taken together, these findings highlight the significant modulations of contrast ratio on metacontrast masking at intermediate<\/p>\n
SOA values. Nevertheless, these alterations were not indicated by the studied event-related potentials and components.<\/p>\n","protected":false},"excerpt":{"rendered":"
\u201cNeurophysiological Investigation of Contrast Ratio Effects on Metacontrast Masking\u201d MS in Neuroscience, Bilkent University Advisor: Asst. Prof. Hulusi Kafal\u0131g\u00f6n\u00fcl The defense will be on August 26th (Thursday), @ 3:00 pm Access Link: https:\/\/zoom.us\/j\/96047419957?pwd=bWdjVDRjMisyVFZmTVYvbExnVHo3UT09 Meeting ID: 960 4741 9957 (Passcode: 896970) Abstract: Visual masking has been used as an investigative tool to […]<\/p>\n","protected":false},"author":7,"featured_media":11641,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[756],"tags":[],"_links":{"self":[{"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/posts\/11730"}],"collection":[{"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/comments?post=11730"}],"version-history":[{"count":4,"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/posts\/11730\/revisions"}],"predecessor-version":[{"id":11734,"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/posts\/11730\/revisions\/11734"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/media\/11641"}],"wp:attachment":[{"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/media?parent=11730"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/categories?post=11730"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/umram.bilkent.edu.tr\/index.php\/wp-json\/wp\/v2\/tags?post=11730"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}