Do younger and older people use the same brain regions to perform cognitive tasks? Can brain activity and structure be altered by mental or physical training? Researchers at the Max Planck Institute for Human Development investigate these questions using the Institute’s magnetic resonance scanner.
Magnetic resonance imaging (MRI) is a procedure to obtain three-dimensional images of anatomic sections of the body. This is done by exploiting the specific magnetic properties of the various types of bodily tissues. These are due to differences in the levels of water and fat in different tissue types or differences in the spatial density of cell membranes, for example. MRI measurement is a non-invasive method requiring neither X-rays nor contrast agents, which means it is particularly low-risk. The Institute’s 3-Tesla MRI scanner is exclusively used for research purposes and not for medical diagnosis.
Before the MeasurementBefore starting, the session is explained to study participants in detail. Depending on the study, tasks may need to be carried out during scanning.
Participant SecurityBefore entering the scanner room, the participants remove all metal objects they are wearing and lock their valuables in a booth. They also receive ear plugs or headphones because of the loud noise of the measurement.
PreparationParticipants are made comfortable with pillows and blankets. Before the measurement itself begins, the button box used for responses is tested. Then the head spool is closed and the gurney is slid into the MRI.
In the MR ScannerDuring the measurement, the upper body of the participants is in the scanner, a tube that is open at both ends and has a diameter of about 60 cm. The participants are asked not to move during scanning so that the brain images obtained are as focused as possible.
Data CollectionThroughout the procedure, the scanning operator remains in contact with the participants via intercom, providing information and asking how they are doing. An alarm button is available should participants want to end the session.
Information for Participants
Magnetic resonance imaging works on the basis of a strong static magnetic field. At the same time, electromagnetic waves in the radio-frequency range are applied during the measurement. As metals can heat up in the MR scanner and metal objects containing cobalt, nickel, or iron are attracted by the magnet, participants with metal foreign objects or implants in their body generally cannot take part in MRI measurements. Furthermore, even traces of these metals can already lead to large-scale image interferences. Nowadays most implants used in medicine, however, are made of titanium, a metal that is not attracted in a magnetic field, meaning that they do not raise health concerns. Nonetheless, the possibility that they may heat up in the scanner cannot be excluded. In order to avoid any risk during scanning, people with metal implants can only participate in MR studies upon detailed clarification of their MR suitability. The easiest way for this to be checked is by providing an implant passport.
The MRI Lab is also equipped with a so-called mock scanner. This is an identical replica of the real scanner without the technology needed for imaging, specifically lacking the magnetic field. This mock scanner is used to allow participants to get used to the situation in the scanner, the tight fit in its tube, and its loud noises.