New studies on the brain—important research findings published over the last 12 months

• After a fatigue-inducing mental task, imaging studies showed decreased brain responsiveness to auditory stimulation (study of 6 male CFS patients and 7 male healthy controls carried out by researchers in Japan). ¹
• Decreased absolute cortical blood flow in the brain (25 CFS patients, 7 controls). When stratified for psychiatric disorders, CFS subjects with psychiatric disorders had decreased blood flow in one region only (left cerebral artery) in contrast to CFS subjects without any psychiatric disorders who had reduced flow in both the right and left middle cerebral arteries. Therefore, those patients having CFS only (devoid of psychopathology) had the largest reduction in flow. ²
• Using more brain physiology to process tasks—A study using BOLD fMRI done in NJ (see the brief summary below). ³
• Reduced grey matter in the brain was linked to reduced activity (study done in the Netherlands of 2 groups of 15 females each, one group was younger than the other). ⁴

Briefly digressing from Dr. Klimas’ lecture, information has been included about the specific findings of the New Jersey study (the 3rd one listed just above) by the researcher herself, Grudin Lange, PhD at one of the afternoon workshops. Lange’s study group, that also included Drs. DeLuca and Natelson (Univ. of Medicine & Dentistry of NJ), looked at mental concentration in CFS patients.

Using a particular type of imaging technique—Blood Oxygen Level Dependent (BOLD) functional MRI, they measured differences in blood flow in the brains of CFS patients compared to controls, especially when challenged with complex auditory processing while doing a simple task. This study shows that people with CFS have to exert more effort to process the same data as healthy controls and provides “evidence of increased neural resource allocation when processing more complex auditory information.”

This conclusion was taken from the study.

Dr. Klimas remarked Japan has become very active in CFS research and that more money is being spent on CFS research there than in the US].

1. Tanaka M et al, “Reduced Responsiveness is an Essential Feature of Chronic Fatigue Syndrome: a fMRI Study,” BMC Neurol Feb 22; 6 (2006): 9.

2. Yoshiuchi K, “Patients with Chronic Fatigue Syndrome have Reduced Absolute Cortical Blood Flow.” Clin Physiol Funct Imaging Mar 26(2) (2006): 83-6.

3. Lange G et al, "Objective Evidence of Cognitive Complaints in Chronic Fatigue Syndrome: a BOLD fMRI Study of Verbal Working Memory," Neuroimage Jun 26(2) (2005):5 13-24.

4. De Lange FP et al, "Gray Matter Volume Reduction in the Chronic Fatigue Syndrome," Neuroimage Jul 1; 26(3)(2005): 777-81.