Susan M. Fitzpatrick

Meeting Report: Transcranial Magnetic Stimulation and Studies of Human Cognition

A James S. McDonnell Foundation workshop1 examined the role of TMS in studies of human cognition. A summary of the workshop presentations, discussion, and the recommendations appear below.2 A selected reference list is provided at the end of the summary.

New Approaches to Functional Neuroenergetics

The coupling between brain energy metabolism andneuronal activity has fo, r more than a century ,allowedresearchers ot monotir brani funcoitn (Roy & Sher-rington, 1890; Siesjo, 1973; Sokoloff, 1981). A break-through in this effort, and one that made human studiesroutine, was the development 20 years ago of positronemission tomography, or PET (see Raichle, 1998). Incombination with experimental paradigms and modelsdeveloped in cognitive psychology, PET allowed the arsthigh-resolution metabolic maps of functionally special-ized regions of the human brain. A drawback of the PETtechnology was its reliance on cyclotron-generatedshort-lived radioisotopes. The subsequent developmentof functional magnetic resonance imaging (fMRI) madefunctional brain mapping widely available to scientists(Kwong et al., 1992; Ogawa, Menon, Kim, & Ugurbil,1992). Almost weekly, new brain imaging results arehighlighted in scientiac journals and the popular mediaas providing new insights into the biological basis ofhuman brain function and neurological and psychiatricdisorders.The application of PET and fMRI to localize cognitiveprocesses is based on the assumption that functionalneuronal activity increases when a region is involved inperforming a cognitive task (Posner & Raichle, 1994).These functional neuronal activities are involved in thecommunication of information between neurons andinclude neurotransmitter release and action potentials.The energy required for these and other brain processesis provided almost exclusively by oxidative glucose me-tabolism (Siesjo, 1978). Functional imaging measureseither glucose metabolism or neurophysiological pa-rameters coupled to glucose metabolism (Sokoloff,1981). Regions of increased functional neuroenergeticdemand are identiaed by the corresponding increase in

Play, attention, and learning: How do play and timing shape the development of attention and influence classroom learning?

The behavioral and neurobiological connections between play and the development of critical cognitive functions, such as attention, remain largely unknown. We do not yet know how these connections relate to the formation of specific abilities, such as spatial ability, and to learning in formal environments, such as in the classroom. Insights into these issues would be beneficial not only for understanding play, attention, and learning individually, but also for the development of more efficacious systems for learning and for the treatment of neurodevelopmental disorders. Different operational definitions of play can incorporate or exclude varying types of behavior, emphasize varying developmental time points, and motivate different research questions. Relevant questions to be explored in this area include, How do particular kinds of play relate to the development of particular kinds of abilities later in life? How does play vary across societies and species in the context of evolution? Does play facilitate a shift from reactive to predictive timing, and is its connection to timing unique or particularly significant? This report will outline important research steps that need to be taken in order to address these and other questions about play, human activity, and cognitive functions.

Meeting Report: Choosing the Right MR Tools for the Job

James S. McDonnell Foundation–sponsored workshops discuss issues concerning functional brain imaging techniques and their use in cognitive neuroscience. Reports from workshops on functional neuroenergetics, the use of transcranial magnetic stimulation, and a workshop on the biological correlates of cognitive functions are available (Recommended Reading 1). This report integrates and summarizes the discussions from two workshops with overlapping interests. The first one was concerned with the statistical analysis of functional magnetic resonance imaging (fMRI) data and the second focused on the advantages and disadvantages of functional imaging at different magnetic field strengths.