Perceptual integration without conscious access.
Johannes J Fahrenfort, Jonathan Van Leeuwen, Christian N L Olivers, Hinze Hogendoorn
Proceedings of the National Academy of Sciences of the United States of America April 4, 2017 Peer reviewed DOI: 10.1073/pnas.1617268114 via PubMed
Summary
The attentional blink impairs conscious decisions about seeing integrated surfaces from fragmented visual input, but brain activity (EEG) still decodes the presence of those integrated percepts. Masking, however, disrupts both conscious decisions and neural decoding of integration. This shows that access consciousness and perceptual integration can be dissociated.
Study at a glance
| Design | experimental study |
|---|---|
| Key finding | Access consciousness and perceptual integration can be dissociated: the attentional blink impairs conscious access but not neural decoding of integrated percepts, whereas masking impairs both. |
Abstract
The visual system has the remarkable ability to integrate fragmentary visual input into a perceptually organized collection of surfaces and objects, a process we refer to as perceptual integration. Despite a long tradition of perception research, it is not known whether access to consciousness is required to complete perceptual integration. To investigate this question, we manipulated access to consciousness using the attentional blink. We show that, behaviorally, the attentional blink impairs conscious decisions about the presence of integrated surface structure from fragmented input. However, despite conscious access being impaired, the ability to decode the presence of integrated percepts remains intact, as shown through multivariate classification analyses of electroencephalogram (EEG) data. In contrast, when disrupting perception through masking, decisions about integrated percepts and decoding of integrated percepts are impaired in tandem, while leaving feedforward representations intact. Together, these data show that access consciousness and perceptual integration can be dissociated.