Title: Contextual associations in visual recognition and memory
Description: Objects in our environment are clustered in typical contexts. For example, a slot machine is typically found at a casino, along with poker chips, a roulette wheel, playing cards, and dice. Previously, we found that a network of three neural regions is consistently involved in the processing of contextual associations: the parahippocampal cortex (PHC), the retrosplenial complex (RSC), and the medial prefrontal cortex (mPFC; Bar & Aminoff, 2003). Using a cognitive neuroscience approach, combining functional magnetic imaging (fMRI) of healthy participants with cognitive experiments, a collection of three studies explored fMRI activation in the neural regions that process contextual associations, revealing how contextual processing is integrated with memory and visual recognition. The studies demonstrated that processing of contextual associations is an important aspect in visual recognition, and might be a core process involved in the perception of a scene. Moreover, contextual processing at the time of recognizing an object or a scene can have a profound effect on the subsequent memory related to that object or scene.

Study 1 employed a novel learning paradigm to demonstrate the fundamental role of the PHC in processing both spatial and non-spatial contextual associations, and therefore supported our proposal that episodic memory and spatial processing, both attributed to PHC processing, might rely on contextual associations. Study 2 used a subsequent memory paradigm to demonstrate that contextual processing of an object at the time of encoding, reflected in RSC and the mPFC activity, can lead to false recognition of a novel but contextually related object. Study 3 examined how boundary extension, a memory of a scene with wider boundaries than those actually presented (Intraub & Richardson, 1989), can be explained by a contextual processing framework in which activity in the mPFC predicts this type of memory distortion. Taken together, the studies in this dissertation uncover the neural mechanisms underlying contextual processing, helping to provide a framework for future cognitive neuroimaging studies to reveal further insights into the nature, function, and contribution of contextual processing.