Juliet Shafto

"The time course of visual processing of shape-contour type"

Abstract: What factors give rise to category selectivity in the human ventral visual pathway? Recently, studies have demonstrated that face-selective brain areas respond preferentially to curvilinear shapes while place-selective brain areas respond preferentially to rectilinear shapes. It is unclear however, whether the dissociation of curved and rectilinear contours precedes the category-selective responses. One hypothesis is that differentiation of shape-contours is a precursor to the separation of faces and scenes. 

Alternatively, shape-contour sensitivity may be a consequence of divergent processing between faces and scenes. To tease apart these possibilities, we recorded event-related potentials during a simple luminance-change detection task, using images of matched curvilinear and rectilinear patterns, as well as faces, scenes, and objects. 

We observed that curved and rectilinear shape contours give rise to dissociable signals at lateral-occipital electrode sites. However, the signals diverge following the initial divergence of face and scene ERP components. These results suggest that information about shape-contours may not be used for the initial, low-level, segregation of faces and scenes in visual processing. Instead, the separation of shape-contours may be involved in other aspects of visual processing.

Zach Weinberg

"How drugs work: GPCR biology and pharmacology"

Abstract: G-protein coupled receptors (GPCRs) represent almost 5% of all the proteins coded for in the human genome. These moderately sized proteins represent one of the major workhorses of intercellular signaling, playing a role in many essential homeostatic processes. Additionally, GPCRs represent the primary target of almost half of all pharmaceutical drugs currently available. However, despite their ubiquity, much remains to be elucidated about how these complex proteins aid in the communication of signals at a cellular level. This talk will give a broad background on GPCRs, their history in research, their pharmacology, and then will focus on current controversies in the field about how they signal.