Research

Our laboratory’s research investigates the neural substrates and behavioral mechanisms of the cognitive factors – attention, working memory, and executive control – that influence the remarkable perceptual abilities of the human mind.

 

We employ functional MRI studies and behavioral psychophysical experiments, along with computational analysis of information processing to perform these investigations.  NIH- and NSF-supported projects in the lab are currently investigating: the interactions between visual attention and visual memory systems; multisensory (visual and auditory) attentional networks; functional distinctions between subregions of the parietal lobe and frontal lobes; and the effects of training and experience on perceptual-attentional networks.  Much of our work focuses on revealing these mechanisms in healthy young adults, but we are collaborating on research regarding aging individuals, Parkinson’s Disease patients, and individuals with mild Traumatic Brain Injury (mTBI).

 

Attention Networks in the Brain

It is well established that portions of the frontal and parietal lobes work together to support attention and working memory.  However, much of this prior work has only coarsely defined the location and function of the networks. Work in the laboratory focuses on identifying multiple attentional subnetworks and their components, and on isolating the functional roles of the brain regions that comprise each network.  In prior work, we identified two previously unidentified regions in the intraparietal sulcus of the parietal lobe, IPS3 and IPS4, and demonstrated that these regions contain mapped representations of visual space.  Current work in the lab: has identified interleaved auditory and visual attentional networks within human frontal lobes; has identified a parietal lobe network that supports retrieval of long-term memories into working memory to support visual perception; and has investigated how meditation experience may alter the interaction between attention networks.  We are also data-mining the large Human Connectome Project dataset to investigate the variability in these multiple attention networks across a broad population of healthy individuals.  We believe that these characterizations will enable us to extend our attentional network assays to clinical populations.

 

Attention – Memory Interactions

In the realm of perception, the average child outperforms the world’s top supercomputers.  Yet, the human mind is profoundly limited in attentional and short-term memory capacity. Our “mental RAM” capacity is roughly four items – items, not gigabytes or terabytes – and yet we easily out-perform supercomputers. The human mind’s perceptual strengths largely derive from long-term memory, much of it stored as perceptual knowledge, which we rapidly access with little or no conscious awareness.  Human perceptual limitations largely derive from a network of frontal lobe and parietal lobe regions that serve as the backbone of the brain’s attentional network.