In order to examine which activity patterns were related to succe

In order to examine which activity patterns were related to successful classification, we also assessed decoding performance when the feature space was restricted to only those voxels activated during a general linear model (GLM). For this purpose, we retrained the classifier post hoc on a restricted feature space of only those clusters activated in a GLM on the localizer task. Using this approach, we examined whether multivariate or average activity patterns within each cluster drove classifier performance. Finally, to assess if representation selleck compound of object-based attention is distributed across multiple brain regions, we applied multivariate decoders

to individual clusters activated in the GLM. If the object representation is distributed across various brain regions, then these individual clusters should yield poorer decoding performance compared with

whole-brain or GLM-restricted decoders. Because brain state predictions are available for every scan in real-time fMRI, these online detected brain states can be used as neurofeedback to train subjects to modulate their ongoing brain activity. Such brain-state dependent stimulation provides a new avenue for investigating the neuronal substrate of cognition (Hartmann et al., 2011; Jensen et al., 2011). To ascertain how this brain-state dependent stimulation impacted subjects’ task performance, we conducted each attention trial twice, once with fMRI neurofeedback and once without it. However, find more due to the lack of statistically significant differences between feedback and non-feedback conditions, we will focus primarily on the non-feedback condition and refer the reader to the Supporting Information for a detailed analysis of the feedback condition. Results for both the

feedback and non-feedback conditions showed that object-based attention can be successfully decoded within a real-time fMRI paradigm. Seven subjects (six males, one female) with an average age of 23.4 years (SD = 4.6) participated in Docetaxel chemical structure the study. All participants had normal vision, and received either monetary compensation or study credits for their participation. The study was approved by the local ethics committee (Commissie Mensgebonden Onderzoek Regio Arnhem-Nijmegen) and conformed with The Code of Ethics of the World Medical Association (Declaration of Helsinki), printed in the British Medical Journal (18 July 1964). Subjects gave written informed consent before the experiment. To keep them motivated during the experiment, participants were promised a monetary reward if their task performance (i.e. average decoding accuracy) in the experiment exceeded 95%. The stimulus set consisted of color pictures of famous faces and famous places collected from the World Wide Web. Previous studies have shown larger activations for familiar faces and places compared with unfamiliar faces and places, respectively (Shah et al., 2001; Pierce et al., 2004; Rosenbaum et al., 2004).

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