{"created":"2023-06-20T13:23:18.080213+00:00","id":4091,"links":{},"metadata":{"_buckets":{"deposit":"fa882670-dce5-4c0b-86f5-ab26d4fc32dd"},"_deposit":{"created_by":21,"id":"4091","owners":[21],"pid":{"revision_id":0,"type":"depid","value":"4091"},"status":"published"},"_oai":{"id":"oai:ir.soken.ac.jp:00004091","sets":["2:430:22"]},"author_link":["2315","2313","2314"],"item_1_creator_2":{"attribute_name":"著者名","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"岡澤, 剛起"}],"nameIdentifiers":[{}]}]},"item_1_creator_3":{"attribute_name":"フリガナ","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"オカザワ, ゴウキ"}],"nameIdentifiers":[{}]}]},"item_1_date_granted_11":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2013-03-22"}]},"item_1_degree_grantor_5":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_name":"総合研究大学院大学"}]}]},"item_1_degree_name_6":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士（理学）"}]},"item_1_description_12":{"attribute_name":"要旨","attribute_value_mlt":[{"subitem_description":"The surface properties of objects, such as gloss, transparency, and texture, provide important\ninformation about the material characteristics of objects in our visual environment. Previous\npsychophysical studies have revealed that humans can correctly estimate surface properties under\nvarious environments. Some recent studies also suggest that humans may utilize simple image\nstatistics to extract the information regarding surface properties. Recently, to uncover neural\nmechanisms underlying perception of surface properties, some researchers have started to examine\nbrain regions processing surface properties in humans using functional magnetic resonance imaging\n(fMRI) and have found that higher order visual areas in the ventral visual pathway are responsive to\nsurface properties. To fully understand the neuronal processing, physiological studies using\nnon-human primates are indispensable. Previous imaging and electrophysiological studies have\nshown that there are cortical regions selectively responding to object shapes, colors, faces etc. in the\nmacaque visual cortex. However, because there have been few reports on the neuronal responses to\nsurface properties in the macaque, we still lack information about where and how surface properties\nare processed. Thus, in this study, I used functional magnetic resonance imaging (fMRI) to examine\nthe cortical responses to surface properties in the macaque visual cortex. Among various surface\nproperties observed in the real world, I focused on surface gloss which is one of the basic surface\nproperties that can be defined by surface reflectances. To find brain regions responsive to surface\ngloss, I generated images of glossy and matte objects using computer graphics. I also prepared\nscrambled images for controls of local spatial patterns by locally randomizing the luminance phases\nof the images with glossy and matte objects. In total, four conditions, i.e. gloss (G), matte (M),\nscrambled gloss (SG), and scrambled matte (SM), were prepared. I trained two awake macaque\nmonkeys, whose heads were rigidly fixed by headpost, to fixate on a central fixation spot on the\nscreen in the MRI scanner while the images for each condition were presented. In experiment 1, I\ncontrasted the responses to glossy images with those to matte and scrambled images by using a\nconjunction analysis (G > M & G > SG & G > SM). Activation was observed along the ventral\nvisual pathway, including V1, V2, V3, V4, and posterior and central regions in the inferior temporal\n(IT) cortex. In experiment 2, to dissociate the responses to contrasts and gloss, I manipulated the\ncontrasts of images to generate high (H) and low (L) contrast images in both the gloss (G) and\nscrambled gloss (S) conditions. By computing the effect of gloss on the cortical responses irrelevant\nto the contrast levels (HG + LG > HS + LS), I found that the responses of these regions were\nactually modulated by surface gloss and could not be explained by the global contrasts. In the IT\ncortex, it has been shown that there are regions specialized for individual categories such as faces\nand objects. Because I found multiple gloss responsive regions in the IT cortex, in experiment 3, I\nexamined the spatial relationships between the face/object responsive regions and the gloss\nresponsive regions observed in the IT cortex. To this end, I conducted a face/object localizer\nexperiment with the same monkeys used in experiment 1 and 2. I found that, although there were\npartial overlaps, the responses to gloss were distinct from those to faces and objects in the IT cortex.\nI also confirmed that responses to glossy images were not observed in higher order areas in the\ndorsal visual pathway (MT+ and intraparietal sulcus), suggesting that the surface gloss is\npredominantly processed in the ventral visual pathway at least in the passive viewing condition. In\nsummary, these results suggest that image features related to glossy surface are processed along the\nventral visual pathway from V1 to specific regions in the IT cortex. This is consistent with previous\nhuman fMRI experiments that showed surface properties are processed in the ventral visual pathway.\nBecause the responses to glossy images could not be explained by the contrasts of images, other\nimage features specifically related to surface gloss would be processed in these areas. In the IT\ncortex, because the gloss responsive regions were distinct from the face and object responsive\nregions, specialized neural substrates may exist to process surface properties of objects.","subitem_description_type":"Other"}]},"item_1_description_7":{"attribute_name":"学位記番号","attribute_value_mlt":[{"subitem_description":"総研大甲第1611号 ","subitem_description_type":"Other"}]},"item_1_select_14":{"attribute_name":"所蔵","attribute_value_mlt":[{"subitem_select_item":"有"}]},"item_1_select_8":{"attribute_name":"研究科","attribute_value_mlt":[{"subitem_select_item":"生命科学研究科"}]},"item_1_select_9":{"attribute_name":"専攻","attribute_value_mlt":[{"subitem_select_item":"20 生理科学専攻"}]},"item_1_text_10":{"attribute_name":"学位授与年度","attribute_value_mlt":[{"subitem_text_value":"2012"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"OKAZAWA, Gouki","creatorNameLang":"en"}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-02-26"}],"displaytype":"simple","filename":"甲1611_要旨.pdf","filesize":[{"value":"279.5 kB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"要旨・審査要旨","url":"https://ir.soken.ac.jp/record/4091/files/甲1611_要旨.pdf"},"version_id":"f68158ad-0dca-4201-b73a-116467d48f2d"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2013-11-26"}],"displaytype":"simple","filename":"学位論文.pdf","filesize":[{"value":"5.5 MB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"Fulltext","url":"https://ir.soken.ac.jp/record/4091/files/学位論文.pdf"},"version_id":"466ec4ff-2c73-4c27-9c09-060c5a0a7ca1"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"thesis","resourceuri":"http://purl.org/coar/resource_type/c_46ec"}]},"item_title":"Localization of regions activated by surface gloss in macaque visual cortex using fMRI","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Localization of regions activated by surface gloss in macaque visual cortex using fMRI"},{"subitem_title":"Localization of regions activated by surface gloss in macaque visual cortex using fMRI","subitem_title_language":"en"}]},"item_type_id":"1","owner":"21","path":["22"],"pubdate":{"attribute_name":"公開日","attribute_value":"2013-11-26"},"publish_date":"2013-11-26","publish_status":"0","recid":"4091","relation_version_is_last":true,"title":["Localization of regions activated by surface gloss in macaque visual cortex using fMRI"],"weko_creator_id":"21","weko_shared_id":21},"updated":"2023-06-20T15:14:37.849556+00:00"}