The University of Colorado MEG Lab
The MEG lab was established in 1975 when Martin Reite, with help from James Zimmerman, Jochen Edrich and John Thomas Zimmerman (no relation to James) successfully recorded magnetic alpha rhythms from six subjects at the National Bureau of Standards (NBS) Boulder Laboratory (Reite et.al., 1976). In 1978 the lab reported the first auditory evoked field data (Reite et al., 1978). The lab was located at NBS in Boulder until 1982 when it moved to The University of Colorado Medical School in Denver. Peter Teale joined the group to assume engineering responsibilities in 1981, in time to assist with the relocation, and the design and fabrication of the new shielded room in Denver. Gradiometers designed and built by James Zimmerman were used exclusively from 1975 through 1984, most notably a transverse gradiometer constructed of bulk Niobium alloy using RF modulation and a ‘point contact’ screw to realize the Josephson junction. In 1984 a second order axial instrument utilizing a DC SQUID was purchased from S.H.E. Corp. in San Diego (the precursor of Biomagnetic Technologies, Inc., BTI). This device was used until 1990, and was used to establish the reduced asymmetry in anterior-posterior laterality of the auditory source of the M50 evoked field in schizophrenic males in 1988 (Reite et. al., 1988), and then a similar finding for the M100 (Reite et al., 1989). A seven channel system was purchased from BTI in 1990 and the aluminum magnetically shielded room (MSR) was lined with 2 mm thickness mu-metal to reduce the DC field artifact. The group continued to explore the relative location of mid and late latency auditory sources in both normal controls and people with schizophrenia through the early 1990’s. During this period it became increasingly common to acquire structural magnetic resonance imaging (MRI) data on all subjects and to co-locate the MEG determined sources on the respective neuroanatomy (usually referred to as Magnetic Source Imaging). Using this methodology the reduction in anterior-posterior hemispheric asymmetry in schizophrenic patients was further refined (Reite et al., 1997). In an effort to develop an animal model to explore these findings the lab recorded the first auditory evoked fields in non-human primates (macaque monkeys, Teale et al., 1994).
Don Rojas joined the lab in 1995, supplying a new energy as well as improved in-house statistical capability. Around the same time the lab expanded its’ focus on mental illness to include children, people with autism, schizoaffective and bipolar disorder. In 1998 a 37 channel Magnes I sensor array was purchased from BTI and installed in the lab-built MSR (called ‘the Igloo’ by BTI personnel). This instrument was used to investigate auditory tonotopy, auditory steady state responses, and auditory evoked field source locations in the previously mentioned subject groups. In 2003 the lab acquired a new 4 layer (alternating 8 mm Al and 3 mm mu-metal panels) MSR built by Lindgren RF Enclosures, and a 248 channel whole head sensor array made by 4D Neuroimaging (descendent of BTI) . Eugene Kronberg joined the lab about this time to provide greater support in physics and computer programming. Work continued in the mental illness categories and now with the ability to record from the entire head at one time the lab began to offer focal epilepsy localization to patients with drug resistant seizure disorders. In 2008 Martin Reite stepped down as director of the lab and Don Rojas replaced him. The next six years saw steady progress in evaluating oscillatory mechanisms (primarily gamma and beta band) in the auditory, somatosensory, and motor cortices in people with psychosis and autism. Isabelle Buard started working with the group in 2010 exploring oscillatory activity and connectivity in subjects with autism, and then investigating auditory-motor entrainment in people with Parkinson’s disease. In 2014 Benzi Kluger replaced Don Rojas as director and the lab moved from the department of Psychiatry to Neurology. The departmental move was accompanied by a shift in focus from mental illness to movement disorders, particularly Parkinson’s disease, while clinical work with epilepsy patients ramped up as the lab’s expertise in this area increased. In 2019 Benzi Kluger left the lab and leadership was split between Archana Shrestha as Clinical Director and Isabelle Buard as Research Director.
The MEG lab in Denver has been involved in many MEG “firsts”. These include first recording of the magnetic equivalent of the P50 auditory evoked magnetic field (Reite et al. 1978), and the first published MEG recordings in non-human primates (Teale et al. 1994). Several patient populations were first studied in Denver with MEG as well: 1) patients with schizophrenia (Reite et al., 1988), 2) schizoaffective disorder (Reite et al., 1999a), 3) bipolar disorder (Reite et al., 1999b) and 4) Fragile X syndrome (Rojas et al., 2001).
References
- Reite, M., Zimmerman, J.E., Edrich, J. and Zimmerman, J.T. The human magnetoencephalogram: some EEG and related correlations. Electroenceph. clin. Neurophysiol., 40: 59—66, 1976.
- Reite, M., Edrich, J., Zimmerman, J.T. and Zimmerman, J.E. Human magnetic auditory evoked fields. Electroenceph. clin. Neurophysiol., 45: 114-117, 1978.
- Reite, M., Teale, P., Zimmerman, J., Davis, K., Whalen, J., Edrich, J. Source origin of a 50 msec latency auditory evoked field component in young schizophrenic males. Biol. Psychiat. 24:495-506, 1988.
- Reite, M., Teale, P., Goldstein, L., Whalen, J., Linnville, S. Late auditory magnetic sources may differ in the left hemisphere of schizophrenic patients: A preliminary report. Arch. Gen. Psychiat. 46:565-572, 1989.
- Reite, M., Teale, P., Rojas, D. C., Sheeder, J., & Arciniegas, D. (1999a). Schizoaffective disorder: evidence for reversed cerebral asymmetry. Biological Psychiatry, 46(1), 133–136.
- Reite, M., Teale, P., Rojas, D. C., Arciniegas, D., & Sheeder, J. (1999b). Bipolar disorder: anomalous brain asymmetry associated with psychosis. American Journal of Psychiatry, 156(8), 1159–1163.
- Reite, M., Sheeder, J., Teale, P., Adams, M., Richardson, D., Simon, J., Rojas. D.C. Magnetic source imaging evidence of sex differences in cerebral lateralization in schizophrenia. Arch. Gen. Psychiat., 54:433-440, 1997.
- Rojas, D. C., Benkers, T. L., Rogers, S. J., Teale, P. D., Reite, M. L., & Hagerman, R. J. (2001). Auditory evoked magnetic fields in adults with fragile X syndrome. NeuroReport, 12(11), 2573–2576.
- Teale, P., Delmore, J., Simon, J., Reite, M. Magnetic auditory source imaging in macaque monkey. Brain Res. Bull., 33:615-620, 1994.