Koivisto Mika, Kahila Ella
Department of Psychology, University of Turku, Assistentinkatu 7, 20014 Turku, Finland.
Department of Psychology, University of Turku, Assistentinkatu 7, 20014 Turku, Finland.
Vision Res. 2017 Apr;133:73-80. doi: 10.1016/j.visres.2017.01.005. Epub 2017 Feb 20.
Top-down processes are widely assumed to be essential in visual awareness, subjective experience of seeing. However, previous studies have not tried to separate directly the roles of different types of top-down influences in visual awareness. We studied the effects of top-down preparation and object substitution masking (OSM) on visual awareness during categorization of objects presented in natural scene backgrounds. The results showed that preparation facilitated categorization but did not influence visual awareness. OSM reduced visual awareness and impaired categorization. The dissociations between the effects of preparation and OSM on visual awareness and on categorization imply that they influence at different stages of cognitive processing. We propose that preparation influences at the top of the visual hierarchy, whereas OSM interferes with processes occurring at lower levels of the hierarchy. These lower level processes play an essential role in visual awareness.
自上而下的加工过程被广泛认为在视觉觉知（即看见的主观体验）中至关重要。然而，以往的研究并未尝试直接区分不同类型的自上而下的影响在视觉觉知中的作用。我们研究了自上而下的准备状态和客体替代掩蔽（OSM）对呈现于自然场景背景中的物体进行分类时的视觉觉知的影响。结果表明，准备状态促进了分类，但并未影响视觉觉知。客体替代掩蔽降低了视觉觉知并损害了分类。准备状态和客体替代掩蔽在视觉觉知和分类上的影响之间的分离意味着它们在认知加工的不同阶段产生影响。我们提出，准备状态在视觉层级的顶端产生影响，而客体替代掩蔽干扰了在层级较低水平上发生的过程。这些较低水平的过程在视觉觉知中起着至关重要的作用。
