EEG during aiming in elite archers: Trembach 2019 study

Five high-level archers, studied by a group at the Kuban sports university in Russia, shot 60 arrows each while a wireless electroencephalogram (EEG) recorded their brain activity during aiming. The authors split the shots into two groups, tens and sevens or eights, and compared the power of brain electrical activity across frequency bands before each kind of shot.

On their reading, tens were preceded by more low-frequency activity over the central frontal areas and a lateral visual area, and by more high-frequency activity in the left hemisphere, over frontal, premotor, parietal and visual areas. Before the less accurate shots the rise in the 4 to 8 Hz band was missing, while high-frequency activity spread over both hemispheres, although in the body of the text the authors describe it as little different from that before the tens. Two archers had shot very few poor arrows (4 and 6), and for them the low-frequency differences were not significant. The results are described only in words: the paper gives no power values and no statistics.

EEG was recorded from 19 sites on the international 10-20 system, at rest and during aiming. For each archer the authors computed average topographic maps of spectral power in five bands (4 to 8 Hz, 8 to 10, 10 to 12, 12 to 24 and 24 to 35), separating tens from sevens and eights, and tested the differences with one-way analysis of variance. The group maps keep only the changes that went the same way in all five athletes, a choice the authors say reduces variability.

The number of shots in each category varied from archer to archer and is not reported, except for the two athletes with 4 and 6 poor shots. The paper does not give the distance, bow type, sex or age of the athletes, how the start and end of aiming were defined, or how artefacts were handled.

This is a five-page paper in the proceedings of a multidisciplinary conference, sharing the volume with economics, law and engineering; the venue is flagged in the registry for questionable editorial standards. Five archers, an undeclared and uneven number of shots per category and no numbers in the results mean the reader can check neither the size of the differences nor how robust they are. Nines are left out without explanation.

The link between frequency bands and functions such as working memory, attention or automated movement comes from the literature cited, not from anything measured here. The closing suggestion of using these signals for biofeedback is likewise the authors' idea and was not tested. In the same year the same group presented an abstract at another conference on four archers with 60 shots each and a similar design; it is unclear whether the data partly overlap.

For an archer the study changes nothing concrete. It describes, in words, that brain electrical activity during aiming differs before a ten and before a seven or eight, an idea other studies on archers have measured in more detail, particularly for low-frequency frontal activity. With five athletes and no numbers, though, it cannot say which pattern is the favourable one for an individual archer, or that training it would add points. In the registry it counts as one more hint within a line of research, not as a basis for neurofeedback programmes.