Methodology

Event-Related Potentials (ERPs)

Our laboratory is best known for its ERP studies. ERPs are electrical responses elicited by stimuli that can be recorded from the scalp in normal subjects. Recording ERPs allows us to measure the effects of attention on specific stages of processing. We are also using ERPs to examine how perceptual information is compared with working memory representations.

• Learn more about the ERP technique.
• View a sample stimulus set.
• Articles that focus on ERP data.
• Articles that focus on ERP methods, components, or localization.

Behavioral Studies

Much of our research involves traditional behavioral measures of processing. Behavioral experiments are relatively quick and simple, so they are a good first approach when addressing a new topic. We also try to provide converging behavioral evidence for our ERP findings to reinforce the validity of these findings and to reach the broadest possible audience.

• View sample stimuli from a working memory experiment.
• Articles that focus on behavioral data.

Magnetoencephalography (MEG)

It is difficult to localize the neural generators of ERP activity, and this is partly caused by the high resistance of the skull. The electrical ERP activity is accompanied by magnetic field fluctuations, and these can be more precisely localized because the skull is transparent to magnetism. We collaborate with the Heinze lab in Magdeburg, Germany on studies using MEG to localize brain activity.

• Link to Heinze Lab
• Articles that discuss MEG.

Other Methods

• We are studying the development of visual working memory during the first year of life in collaboration with the laboratory of Prof. Lisa Oakes.
• We are studying deficits of attention and working memory in patients with schizophrenia in collaboration with Dr. James M. Gold of the Maryland Psychiatric Research Center.
• We are working with a computational neuroscientist, Antonino Raffone, to construct detailed neural network models of attention.
• We are testing lesion patients at the University of Iowa Hospitals and Clinics to explore the neural substrates of visual working memory.
• We are working with two neurologists, Erik St. Louis and Deepak Madhaven, to record ERPs from a variety of neurological patients.