Perception and semantics in the ventral stream

One of the goals of cognitive neuroscience is to understand how we process visual objects, and what functional contributions different neural regions make. Our ability to perceive and interact with the world critically relies on the ventral processing stream through occipital and temporal cortices with increasingly anterior portions of the ventral stream responding to increasingly complex stimuli (Taylor, Moss & Tyler, 2007; Felleman & Van Essen, 1991; Tanaka, 1996; Tsunoda et al., 2001). As such, there is a relatively detailed account of how we process objects in a visual sense. However, an aspect of object recognition that is largely avoided concerns what an object means - it’s associated semantic knowledge. Instead, the dominant research strategy is to either focus on object recognition as a purely visual phenomenon, or study semantics without recourse to visual effects.

Recognising what a visual object is not only requires that objects are processed visually, but also that the semantic knowledge associated with the object is evoked. As such, a comprehensive account of how we recognise what an object is requires bringing together theories of visual object recognition, and cognitive models of semantic knowledge within the same neurobiological framework. This is the approach we’ve been developing (see Taylor, Moss & Tyler, 2007 for review) - understanding not only the cognitive contributions of different brain regions, but also how meaning emerges across time (e.g. Clarke, Taylor & Tyler, 2011). Uncovering how we understand what we see requires the development of a comprehensive systems-level account of how we get from perceiving an object, to understanding what it is, and requires the synthesis of cognitive theories and neurobiological models - a fundamental component of cognitive neuroscience.

Clarke, A., Taylor, K.I., & Tyler, L.K. (2011). The evolution of meaning: Spatiotemporal dynamics of visual object recognition Journal of Cognitive Neuroscience, 23(8), 1887-1899.

Felleman, D. J., & Van Essen, D. C. (1991). Distributed hierarchical processing in the primate cerebral cortex. Cerebral Cortex, 1, 1-47.

Tanaka, K. (1996). Inferotemporal cortex and object vision. Annual Review of Neuroscience, 19, 109-140.

Taylor, K. I., Moss, H. E., & Tyler, L. K. (2007). The conceptual structure account: a cognitive model of semantic memory and its neural instantiation. In J. Hart & M. Kraut (Eds.), The neural basis of semantic memory (pp. 265-301). Cambridge: Cambridge University Press.

Tsunoda, K., Yamane, Y., Nishizaki, M., & Tanifuji, M. (2001). Complex objects are represented in macaque inferotemporal cortex by the combination of feature columns. Nature Neuroscience, 4(8), 832-838.