The human ability to rapidly recognize the local visual environment, or ?scene?, forms the bedrock for many of our essential, everyday behaviors. In a brief glance, we extract a wealth of information from scenes, such as the category of the scene (e.g., ?a city?), its identity (e.g., ?Atlanta?), and other critical properties like whether it is safe or what behavior is appropriate for the current context. Almost simultaneously, we also extract information that is vital for navigation, allowing us to find our way through the local visual environment flawlessly and effortlessly, not running into walls or tripping over obstacles. What?s more, we immediately realize the local visual environment within a broader spatial map, allowing us, for example, to find our way home from the newest restaurant in another part of town. But how do we accomplish these remarkable feats? One promising strategy for attempting to understand human visual scene processing is to characterize the neural system that accomplishes it. Thus, the long-term objective of this research is to understand the neural mechanisms involved in human visual scene processing, from childhood to adulthood, in health and disease. Cognitive neuroscience of the past two decades has revealed a set of three cortical regions that together make up the human visual scene processing system: the parahippocampal place area (PPA), the retrosplenial complex (RSC), and the occipital place area (OPA). However, beyond establishing the general involvement of these regions in scene perception (i.e., responding more to images of scenes than to images of everyday objects or faces in human neuroimaging experiments), three fundamental and yet unanswered questions remain. First, what is the precise function of each region in adult human visual scene processing? Is each region playing a part in all the elements of human visual scene processing (i.e., scene categorization, visually-guided navigation, and map-guided navigation, as described above), or instead does each have its own distinct function? Second, how does this functional organization breakdown under neurological insult? And third, how does it get wired up in development? This research will aim to address these three questions using a variety of methods and participant populations, including functional magnetic resonance imaging (fMRI) and psychophysics in healthy adults, healthy children, and individuals with Williams syndrome (a genetic disorder), as well as transcranial magnetic stimulation (TMS) in healthy adults. Understanding human visual scene processing and its development, in health and disease, is not only of inherent scientific interest, but also may someday be harnessed to help those individuals who devastatingly lose the ability to recognize their environment and navigate through it, as a result of eye diseases, brain surgery, stroke, neurodegenerative diseases, or developmental disorders.
The ability to recognize our environment and navigate through it is crucial to our survival, and hence losing this ability is devastating. As such, this research ? with the goal of understanding the neural mechanisms involved in our critical ability to recognize places or ?scenes? (e.g., a kitchen, a beach, our house) and navigate through such space, from childhood to adulthood, in health and disease ? will hopefully inform i) neurosurgeons about what precise pieces of cortex support what precise functions, which will certainly help in identifying what regions to avoid removing during surgery as a result of tumor resection or epilepsy, or anticipating what functions will be lost if the removal of such regions are unavoidable, and ii) ophthalmologists, optometrists, neurologists, clinical neuropsychologists, and physical and occupational therapists about remediation and rehabilitation efforts in individuals who lose the ability to recognize and navigate their environment as a result of eye diseases (e.g., Macular Degeneration), brain surgery, stroke, neurodegenerative diseases (e.g., Alzheimer?s disease), or developmental disorders (e.g., Williams syndrome). For example, identifying precisely which abilities are spared versus impaired in a particular disorder (e.g., categorization versus navigation in Williams Syndrome) introduces the possibility of using those spared abilities to ?bootstrap? learning of impaired abilities.
