Is there a relationship between fetal brain function and the fetal behavioral state? A fetal MEG-study.

AIM: Fetal magnetography enables the recording of biomagnetic fetal signals, including fetal heart and fetal brain signals. These signals allow the determination of fetal behavioral states and functional brain signals with auditory evoked responses (AER). In the current study, we investigated how the behavioral state influences the AER and how stimulation affects fetal state. METHODS: One hundred and four fetuses in three age groups (28-31 weeks, 32-35 weeks and 36-41 weeks) were recorded with and without auditory stimulation. Both sessions were scored for fetal states. The AER latency was determined for each state separately. Forty-five additional subjects were recorded with two sessions of 10 min without stimulation to investigate a possible time effect on state changes. RESULTS: The state distribution was significantly different between stimulation and no stimulation conditions. The AER latencies were significantly shorter in active sleep (P=0.013) and active wakefulness (P=0.004) compared to quiet sleep. CONCLUSION: Auditory stimulation has an effect on fetal states. The state information should be taken into account for the analysis of AER latencies.

Weighted phase lag index and graph analysis: preliminary investigation of functional connectivity during resting state in children.

Resting state functional connectivity of MEG data was studied in 29 children (9-10 years old). The weighted phase lag index (WPLI) was employed for estimating connectivity and compared to coherence. To further evaluate the network structure, a graph analysis based on WPLI was used to determine clustering coefficient (C) and betweenness centrality (BC) as local coefficients as well as the characteristic path length (L) as a parameter for global interconnectedness. The network's modular structure was also calculated to estimate functional segregation. A seed region was identified in the central occipital area based on the power distribution at the sensor level in the alpha band. WPLI reveals a specific connectivity map different from power and coherence. BC and modularity show a strong level of connectedness in the occipital area between lateral and central sensors. C shows different isolated areas of occipital sensors. Globally, a network with the shortest L is detected in the alpha band, consistently with the local results. Our results are in agreement with findings in adults, indicating a similar functional network in children at this age in the alpha band. The integrated use of WPLI and graph analysis can help to gain a better description of resting state networks.

Brain Painting: First Evaluation of a New Brain-Computer Interface Application with ALS-Patients and Healthy Volunteers.

Brain-computer interfaces (BCIs) enable paralyzed patients to communicate; however, up to date, no creative expression was possible. The current study investigated the accuracy and user-friendliness of P300-Brain Painting, a new BCI application developed to paint pictures using brain activity only. Two different versions of the P300-Brain Painting application were tested: A colored matrix tested by a group of ALS-patients (n = 3) and healthy participants (n = 10), and a black and white matrix tested by healthy participants (n = 10). The three ALS-patients achieved high accuracies; two of them reaching above 89% accuracy. In healthy subjects, a comparison between the P300-Brain Painting application (colored matrix) and the P300-Spelling application revealed significantly lower accuracy and P300 amplitudes for the P300-Brain Painting application. This drop in accuracy and P300 amplitudes was not found when comparing the P300-Spelling application to an adapted, black and white matrix of the P300-Brain Painting application. By employing a black and white matrix, the accuracy of the P300-Brain Painting application was significantly enhanced and reached the accuracy of the P300-Spelling application. ALS-patients greatly enjoyed P300-Brain Painting and were able to use the application with the same accuracy as healthy subjects. P300-Brain Painting enables paralyzed patients to express themselves creatively and to participate in the prolific society through exhibitions.