While caffeine's ability to reduce cerebral blood flow has already been established, researchers from the University of Wisconsin at Madison report that common levels of coffee consumption can alter functional MR results and demand special efforts to control for caffeine effects. Those who have recently stopped drinking coffee are not excepted: The study illustrates that caffeine withdrawal also affects cerebral blood flow enough to skew imaging findings.

While caffeine consumers may experience a sped-up reality, researchers in Long Beach, CA, conclude that faster task performance in the brain correlates to less brain activity. Individuals in the study viewed a line drawing on an LCD with an accompanying description. They then pressed one button when the stimuli matched and another key if they did not match. This functional MRI investigation of a visuomotor task found a significant correlation between the mean reaction time for task performance and the number of activated voxels for individuals in the study.

Brain imaging research in Seattle, WA, is uncovering new evidence on how deaf people perceive sound. Studying fMRI activation in the brains of deaf students exposed to low-frequency sounds (such as the bass component of loud music), researchers have found that low-frequency vibrational sensations may be "heard" by deaf listeners in the auditory cortex. The imagers hypothesize that the effect reflects early cortical reorganization possibly analogous to the visual cortex activity observed during the reading of Braille in blind subjects.

--By Merlina Trevino