Using fMRI Brain Activation to Identify Cognitive States Associated with Perception of Tools and Dwellings

Abstract

Previous studies have succeeded in identifying the cognitive state corresponding to the perception of a set of depicted categories, such as tools, by analyzing the accompanying pattern of brain activity, measured with fMRI. The current research focused on identifying the cognitive state associated with a 4s viewing of an individual line drawing (1 of 10 familiar objects, 5 tools and 5 dwellings, such as a hammer or a castle). Here we demonstrate the ability to reliably (1) identify which of the 10 drawings a participant was viewing, based on that participant's characteristic whole-brain neural activation patterns, excluding visual areas; (2) identify the category of the object with even higher accuracy, based on that participant's activation; and (3) identify, for the first time, both individual objects and the category of the object the participant was viewing, based only on other participants' activation patterns. The voxels important for category identification were located similarly across participants, and distributed throughout the cortex, focused in ventral temporal perceptual areas but also including more frontal association areas (and somewhat left-lateralized). These findings indicate the presence of stable, distributed, communal, and identifiable neural states corresponding to object concepts.

Exploring commonalities across participants in the neural representation of objects

“…High classification accuracies for the two categories [Shinkareva et al, 2008] have been previously shown for the whole brain (single large scale ROI). In this work we are introducing the analysis of interobject distances based on the whole brain (single large scale ROI).…”

“…The RV-coefficient has been previously used in the neuroimaging literature [Abdi et al, 2009;Glascher et al, 2009;Kherif et al, 2003;O'Toole et al, 2007;Shinkareva et al, 2006Shinkareva et al, , 2008 and is described in detail in Abdi [2007] and Ramsay et al [1984]. It measures the overall similarity of two matrices and is analogous to a squared coefficient of correlation.…”

“…We examine the commonality in neural representation of objects across participants on an fMRI data set reported in Shinkareva et al [2008]. Twelve participants viewed line drawings of 10 objects from tools and dwellings categories.…”

“…Using multivoxel pattern analysis, previous studies succeeded in identifying the cognitive states associated with viewing categories of objects [Carlson et al, 2003;Cox and Savoy, 2003;Hanson and Halchenko, 2007;Hanson et al, 2004;Haxby et al, 2001;O'Toole et al, 2005;Polyn et al, 2005]. Moreover, the category of an object that a participant was viewing [Shinkareva et al, 2008[Shinkareva et al, , 2011 or a concrete noun that a participant was reading [Just et al, 2010;Shinkareva et al, 2011] can be identified based only on other participants' characteristic neural activation patterns, establishing the commonality in how different people's brains represent the same object. The similarity of object representation across individuals is of particular interest.…”

“…Second, STATIS is based on the cross-product matrix, thus allowing the number of voxels that are used in the analysis to vary between participants. The STATIS procedure has been shown to be robust and computationally efficient [Stanimirova et al, 2004], and has been previously applied in neuroimaging literature [Abdi et al, 2009;O'Toole et al, 2007;Shinkareva et al, 2008]. For nonneuroimaging in-depth treatment of the STA-TIS procedure the reader is referred to Abdi and Valentin [2007].…”