For ethical reasons, neuro-scientific research on humans is for the most part confined to non-invasive methods. However, constant innovation in imaging technology and image analysis allows increasingly detailed insight into the human brain.
Improving both spatial and temporal resolution is the driving force behind such technological developments. Additionally, combining different modalities, for example MRI with EEG or MRI with PET, will allow a much more comprehensive understanding of neuronal processes in the brain.
The Combinatorial NeuroImaging core facility offers open access to ultra high-field magnetic resonance tomography. We provide modern MR coil technology and all common MR sequences. For functional imaging, we provide high quality visual and auditory stimulation systems as well as monitoring devices for recording physiological parameters and the behavior of subjects
7 Tesla Magnetic Resonance Imaging
The Leibniz Institute for Neurobiology operates Europe's first 7 Tesla magnetic resonance scanner for human studies. The system was installed in a specially constructed building adjacent to the LIN’s main building.
The stronger magnetic field generates a greatly improved single to noise ratio which is about twice as good as that of a 3 Tesla MRI. This stronger signal can be traded for higher spatial resolution of an equal factor. Thus, finer structures of the brain can be studied both anatomically and functionally. Furthermore the higher signal can also be used to reduce the required scan time which is particularly useful for learning studies.
3 Tesla Magnetic Resonance Imaging
Funded by the federal state of Saxony-Anhalt and the European Regional Development Fund (ERDF), the Philips 3T Achieva dStream was put into operation in November 2013. In contrast to the 7T scanner, which is used to visualize specific brain areas, the 3T scanner is particularly suitable for whole brain-fMRI (3 mm Iso, in the future also ≤2 mm with multiband-EPI), as well as anatomic recording. Like our 7 T scanner, the 3 T scanner offers a multitude of special features.
Electroencephalography (EEG) allows detecting the activity of neurons by the generated currents of electrically charged particles (like sodium and potassium) with a high temporal resolution of about one millisecond. An arrangement of special electrodes detects the spatial distribution of the electrical potential generated by the neuronal activity on the surface of the subject’s head. In our lab, several EEG are systems available, including an active 128-electrode device and a MR compatible system.
Moreover, EEG measurements may be combined with multiple peripheral physiological recording and stimulation methods. Multichannel electromyography, i.e. the measurement of the electrical activity of muscles, measurement of skin conductance and breathing movements, and electrocardiography may be used to capture information on emotional states. Eye tracking and the recording of otoacoustic emissions are possible as well. Transcranial electric stimulation can be used to directly modulate brain activity.