5 - (SYM 13) Disturbing Standing Balance to Probe Anxiety-related Brain Activity in Children

Brain activity can reveal biases in cognitive and emotional processing that may contribute to anxiety disorders. The Error-Related Negativity (ERN) is a measurable brain response that occurs after mistakes and can predict the development and exacerbation of anxiety disorders in children. However, this method is limited by relying on individuals to spontaneously commit comparable sequences of mistakes. An externally imposed disturbance to standing balance evokes a larger brain response called the balance N1 that resembles the ERN in scalp topography and moderating factors. We recently found that the balance N1 and ERN were correlated in small samples of younger and older adults. We hypothesized that the balance N1 probes the same brain processes as the ERN and would therefore be enhanced with anxiety.

We assessed N=34 anxious children (age 9-12, with Generalized Anxiety, Social Anxiety, and/or OCD) and N=50 controls. The ERN was measured at frontocentral EEG electrodes as the mean in a 100ms window centered on errors in a go no-go task. The balance N1 was measured as the mean 50-150ms after sudden release of a cable supporting 5% of body weight in a forward leaning posture. Split-half reliabilities assess internal consistencies. One-tailed t-tests assess group differences. Pearson’s product-moment correlations measure associations between the balance N1, ERN, and SCARED-parent report of child anxiety severity, combining children across groups. All tests are repeated across Fz, FCz, and Cz electrodes. The balance N1 was more internally consistent (Fz 0.89 FCz 0.91 Cz 0.92) than the ERN (Fz 0.65 FCz 0.45 Cz 0.34). The balance N1 was larger in the anxious children (Fz p=0.061, FCz p=0.010, Cz p=0.002), while the ERN displayed trends (Fz p=0.224, FCz p=0.074, Cz p=0.052) for this effect. Further, the balance N1 was associated in amplitude with the ERN (Fz r=0.251 p=0.023, FCz r=0.261 p=0.018, Cz r=0.312 p=0.005) and with anxiety severity (Fz r=-0.269 p=0.014, FCz r=-0.292 p=0.007, Cz r=-0.281 p=0.011). The ERN was less robustly associated with anxiety severity (Fz r=-0.200 p=0.070, FCz r=-0.265 p=0.016, Cz r=-0.201 p=0.068). These results suggest the balance N1 provides a more powerful probe of anxiety-related differences in brain activity than the ERN. Further investigation of the balance N1 may provide new insight into observed relationships between anxiety and balance control in terms of neural circuitry, behavior, disorder presentation, and response to treatment, which could lead to new treatment strategies.