Background and Objectives Prolonged screen exposure is often cited as a trigger for pediatric headache. We present initial findings evaluating the association between adolescent screen use type, duration, and school disability. Methods New patients aged 12–17 years presenting to a headache clinic were screened and surveyed regarding headache characteristics, behavioral habits, school attendance, and screen utilization. Results 99 adolescents (29 M, 70 F) with average age 14.8 years and average headache frequency of 17 days per month completed the survey. Patients missed an average of five full days and three partial days of school due to headaches over the 90 days prior to survey completion. No statistically significant correlation was found between type or duration of screen exposure and monthly headache frequency, school attendance, or school functioning. A small positive association was seen between increasing duration of computer use, total hours screen use, and school absenteeism. While most adolescents reported prolonged screen use (58.6%) and luminosity (64.6%) worsened headaches, no statistical difference was seen in average number of headache days per month. Conclusions Average monthly headache frequency in an adolescent population was not significantly correlated with type or duration of screen exposure. Further studies are needed to elucidate how screen utilization impacts school related headache disability.

Background: Motor surround inhibition (mSI) is a phenomenon supportive for executing selective finger movements, wherein synergist muscles are selectively facilitated while surround muscles are inhibited. Previous studies of conditioning inputs to several intracortical and cortico-cortical inhibitory networks did not show an influence on mSI. The inhibitory posterior parietal-motor network, which is crucial for executing fine movements, however, has not been studied. Objective/hypothesis: To investigate the role of inhibitory posterior parietal-motor network in mSI. We hypothesized that conditioning this inhibitory network would enhance mSI. Methods: 11 healthy adults completed study. mSI was elicited by applying a TMS pulse over the motor cortex coupled with or without a conditioning input to an inhibitory spot in the posterior parietal cortex at 2 or 4 ms interval. Results: Conditioning input to the posterior parietal cortex increased mSI by~20% Conclusion: The inhibitory posterior parietal-motor network appears to contribute to the genesis of mSI.

Functional integration between two hemispheres is crucial for perceptual binding to occur when visual stimuli are presented in the midline of the visual field. Mima and colleagues (2001) showed using EEG that midline object recognition was associated with task-related decrease in alpha band power (alpha desynchronisation) and a transient increase in interhemispheric coherence. Our objective in the current study was to replicate the results of Mima et al. and to further evaluate interhemispheric effective connectivity during midline object recognition in source space. We recruited 11 healthy adult volunteers and recorded EEG from 64 channels while they performed a midline object recognition task. Task-related power and coherence were estimated in sensor and source spaces. Further, effective connectivity was evaluated using Granger causality. While we were able to replicate the alpha desynchronisation associated with midline object recognition, we could not replicate the coherence results of Mima et al. The data-driven approach that we employed in our study localised the source of alpha desynchronisation over the left occipito-temporal region. In the alpha band, we further observed significant increase in imaginary part of coherency between bilateral occipito-temporal regions during object recognition. Finally, Granger causality analysis between the left and right occipito-temporal regions provided an insight that even though there is bidirectional interaction, the left occipito-temporal region may be crucial for integrating the information necessary for object recognition. The significance of the current study lies in using high-density EEG and applying more appropriate and robust measures of connectivity as well as statistical analysis to validate and enhance our current knowledge on the neural basis of midline object recognition.