Biomedical Engineering Reference
In-Depth Information
Although the hemoglobin level is outside of its normal range, it may be acceptable clinically. It may
be temporarily elevated if the patient is dehydrated, for example. Making this clinical decision is the
physician's responsibility, based on her experience. However, before the physician can make this
assessment, she must be able to quickly identify values that are significantly out of normal
range—which is where visualization aids are most valuable.
The value of using graphical representations of data to provide added meaning and context is also
evident in the field of neuroscience, where 3D visualization technologies such as functional magnetic
resonance imaging (fMRI) have supplanted the squiggly lines of the electroencephalograph (EEG).
Functional MRI, which is based on the nuclear magnetic resonance of protons to produce proton
density maps, empowers researchers to observe activity in the brain—as a 3D color image of the
gross brain—when the patient is asked to perform different mental tasks. Particular patterns of
activity are also associated with personality traits, from aggression and risk-aversion to depression.
Although these and other data have been available in the form of EEGs, before such advanced
visualization technologies as fMRI, these patterns were not readily discernable, even to researchers
who spent most of their time interpreting EEGs. Thanks to fMRI, researchers and clinicians with only
minimal knowledge of neuroanatomy and neurophysiology can see changes in patterns of color on
the brain surface and correlate the patterns with a patient's mental activity.
A major challenge in molecular biology has long been making sense of an abundance of potentially
confusing data—even prior to the start of automated nucleotide sequencing of the human genome.
Perhaps for this reason, some of the most influential advances in the field have been based on highly
visual research. For example, in performing the basic research that formed the basis for his laws of
