again measure MEG signals. Multimodal neuroimaging Multimodal imaging combines existing brain imaging techniques in synergistic ways which facilitate the improved interpretation of data. Besides fMRI, another example of technology allowing relatively older brain imaging techniques to be even more helpful is the ability to combine different techniques to get one brain map. This happens quite frequently with MRI and EEG scans. The electrical diagram of the EEG provides split-second timing while the MRI provides high levels of spatial accuracy. The combined use of MEG and functional magnetic resonance imaging was first reported in 1999. It combines the spatial resolution of fMRI with the temporal resolution of the MEG. Often the non-uniqueness of the MEG source estimation problem (inverse problem) can be alleviated by incorporating information from other imaging modalities as an a priori constraint. Anatomically constrained MEG (aMEG) uses anatomical MRI data as a geometrical or location constraint and as a medium for visualization of MEG results. MEG does not provide structural or anatomical information. Therefore, MEG data is often combined with MR data into a composite image whereby functional information is overlaid on the corresponding anatomy to produce an activation map. Recent breakthroughs Recent breakthroughs in non-invasive brain imaging have been somewhat limited because most of them have not been completely novel; rather, they are simply refining existing brain imaging techniques. fMRI is a perfect example of this from the early 1990s, and it still remains the most popular brain imaging technique available today. Advances have been made in a number of ways regarding neuroimaging, and this section will cover some of the more prominent improvements including computational advances, transcranial magnetic stimulation, and nuclear magnetic resonance. To begin with, much of the recent progress has had to do not with the actual brain imaging methods themselves but with our ability to utilize computers in analyzing the data. For example, substantial discoveries in the growth of human brains from age three months to the age of fifteen have been made due to the creation of high-resolution brain maps and computer technology to analyze these maps over various periods of time and growth (Thompson, UCLA). This type of breakthrough represents the nature of most breakthroughs in neuroscience today. With fMRI technology mapping brains beyond what we are already understanding, most innovators time is being spent trying to make sense of the data we already have rather than probing into other realms