{"id":375,"date":"2018-03-19T17:11:31","date_gmt":"2018-03-19T17:11:31","guid":{"rendered":"https:\/\/scholarblogs.emory.edu\/sire299thees\/?p=375"},"modified":"2018-03-19T17:18:46","modified_gmt":"2018-03-19T17:18:46","slug":"modeling-affective-bias","status":"publish","type":"post","link":"https:\/\/scholarblogs.emory.edu\/sire299thees\/2018\/03\/19\/modeling-affective-bias\/","title":{"rendered":"Modeling Affective Bias Data"},"content":{"rendered":"<p>Last semester, I left off after reviewing all the video files of four Deep Brain Stimulation (DBS) patients completing the affective bias task during the &#8220;Chronic&#8221; phase of the clinical trial. This is the phase in which their stimulation is constitutively on for a period of 6 months, and during this time they attend weekly testings in which affective bias is administered anywhere from 1 to 4 times in a session. This phase is followed by &#8220;Discontinuation&#8221;, in which stimulation is turned off for a relatively short amount of time that cannot be disclosed to maintain patient objectivity, and patients attend daily testing sessions. The purpose of this phase is to test the long-term effects of the prior stimulation period.\u00a0Due to the ethical constraints that come along with this kind of clinical trial, this off-period is the longest time a patient&#8217;s stimulation can be off. Unfortunately, this period is not always long enough to show the long-term effects of stimulation.<\/p>\n<p>Anyway, now that the video files are ready to be preprocessed and analyzed, we have been waiting to meet with the graduate student who created the machine-learning algorithm that allows for facial analysis. During this waiting time, I have completed the Discontinuation database for Affective Bias for patients 906, 907, and 908. To recap, here are the steps I took to complete this task:<\/p>\n<ul>\n<li>When a patient completes one run of the affective bias task, a matlab file is created with their scores for each face that was rated. During discontinuation, a patient completes the task about 4 times each session, and testing is done everyday for 2 weeks. This equates to about 150 mat lab files that must be compiled into a single database file that can be used for analysis.<\/li>\n<li>To fast track compiling the files, I automated the process using a python script that is able to take multiple .mat files =and input them into a .csv that can be opened in excel. In addition, the script uses information about each face that was rated to calculate an expected value for each face&#8217;s rating.<\/li>\n<li>Once all information from the affective bias task itself was complete in the database, I had to manually input patient Positive and Negative Affective Schedule (PANAS) scores. PANAS, which is a psychiatric tool used as direct measure of depression, is completed at the beginning of each testing session.<\/li>\n<\/ul>\n<p>Now that the database is complete, we can begin building a model for the data. The goal of the model is to use information of the expected rating and of patient depression to predict how a given patient will rate a given face. The outcome variable is a vector of predicted responses. The model that has been used in past affective bias analysis looks something like this:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-376 aligncenter\" src=\"https:\/\/scholarblogs.emory.edu\/sire299thees\/files\/2018\/03\/Screen-Shot-2018-03-19-at-12.24.30-PM-300x37.png\" alt=\"\" width=\"349\" height=\"43\" srcset=\"https:\/\/scholarblogs.emory.edu\/sire299thees\/files\/2018\/03\/Screen-Shot-2018-03-19-at-12.24.30-PM-300x37.png 300w, https:\/\/scholarblogs.emory.edu\/sire299thees\/files\/2018\/03\/Screen-Shot-2018-03-19-at-12.24.30-PM-768x95.png 768w, https:\/\/scholarblogs.emory.edu\/sire299thees\/files\/2018\/03\/Screen-Shot-2018-03-19-at-12.24.30-PM.png 926w\" sizes=\"auto, (max-width: 349px) 100vw, 349px\" \/><\/p>\n<p>where\u00a0<em>Y<sub>i<\/sub> = vector of outcome responses for i<sup>th<\/sup> subject, S<sub>i<\/sub> = stimulation status, E<sub>i\u00a0<\/sub>= expected rating, D<sub>i\u00a0<\/sub>= Hamilton Depression Rating, and y<sub>0i<\/sub> = random intercept.<\/em><\/p>\n<p>Although this is not the exact model we will be using, I will be working with Kelly to tweak the SAS script that was used to implement this regression for prior work. This analysis may end up being a minor focus of my poster given that I have spent a good portion of time this year working on it due to the setbacks in the facial motor analysis.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Last semester, I left off after reviewing all the video files of four Deep Brain Stimulation (DBS) patients completing the affective bias task during the &#8220;Chronic&#8221; phase of the clinical trial. This is the phase in which their stimulation is constitutively on for a period of 6 months, and during this time they attend weekly &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/scholarblogs.emory.edu\/sire299thees\/2018\/03\/19\/modeling-affective-bias\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Modeling Affective Bias Data&#8221;<\/span><\/a><\/p>\n","protected":false},"author":4951,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-375","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/posts\/375","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/users\/4951"}],"replies":[{"embeddable":true,"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/comments?post=375"}],"version-history":[{"count":3,"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/posts\/375\/revisions"}],"predecessor-version":[{"id":380,"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/posts\/375\/revisions\/380"}],"wp:attachment":[{"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/media?parent=375"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/categories?post=375"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/scholarblogs.emory.edu\/sire299thees\/wp-json\/wp\/v2\/tags?post=375"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}