When skiing we set our gaze basically in two areas of our visual field: the proximal zone and the distant zone. Fixating our central vision at the distant zone provides feedforward information about our trajectory, allowing the possibility to adjust it. Instead, fixating vision towards the proximal zone, as being close to us, it may not allow large trajectory adjustments but last moment reactions. In this zone, we use our peripheral vision to monitor our skis, posture, and balance providing feedback information. The advanced skier uses the information of both zones while the beginner tends to focus his vision mostly near the proximal zone.
The proximal zone strategy of visual fixation is usually employed as a reference to determine the imminent direction change point, while distant zone visual fixations establish the prediction of farthest turning points or the destination point (the end of the descent or the slope). According to Lehtonen et al. (2014), the distant zone determines the quality of our motion, which is important for skiing fluidity, and the proximal zone establishes our stabilization level.
The visual fixation to the proximal zone is used, in addition, as a strategy to deal with difficult situations on markedly inclined slopes that we perceive as threatening. In this context, our gaze is exclusively geared towards the closest direction change point, avoiding directing it to the downhill, inhibiting in this way the emotional impact of a frightening vacuity, i.e., the upsetting feeling of spatial emptiness.
Visual fixation mechanisms for trajectory determination
Gaze fixating is an active control mechanism of motion orientation because in the direction our gaze is oriented, our skis will follow (our gaze guides our body and our body guides our skis). With this goal in mind, we generally use two visual mechanisms: one establishes the destination point determining linear or curvilinear trajectories to get to that point, which is taken as a reference for our descent. The other mechanism establishes the direction change point, which is a pretended point where we will modify our linear or curvilinear trajectory.
The destination point is located in the distant zone, being the place we take our run that could be the slope’s end or some area in between, a trails merging, a certain place of a mogul run or a tree in the woods. To plan our descent, we need first to establish the destination point.
The direction change point, in successive turns, is the point of direction reversal in curvilinear trajectories being located in the proximal zone. This point setting determines the end of one turn and the start of the next during linked turning motions. Generally, the destination point is just one while we can determine as many direction change points as we decide.
The beginner skier has an idea of the destination point but still needs practice defining direction change points and to do so, should develop orientation and spatiality consciousness. In the beginning, he establishes direction changes with central vision but then, with training, will use peripheral vision as well.
Gaze function during direction changes
Skiing becomes efficient by orienting our skis to the point of our gaze fixation (we ski where we look). We determine and initiate direction changes by our eyes’ movements. We set our gaze and adjust our skis alignment by steering and edging actions to cover the angle and distance between our skis existing orientation and the turn ending. Generally, the beginner visually determines direction changes in relation to the upper body transverse axis, while the advanced skier does it by taking the skis’ longitudinal axis as a reference.
In carved turns, we usually take as peripheral visual reference our ski tips direction, gradually aligning them towards the destination point or the direction change point. If our intention is to perform skidded turns, then we will take our heels as sensorimotor references, using them to dynamically align our ski tails towards one of the mentioned points. If we do not determine the end point of our future trajectory, we will not be able to define the angle formed between our skis and that point, so it will be difficult to know how much we should turn. This is why it is important to determine the initiation point of the next turn through visual anticipation.
Visual field dependence and independence
Witkin et al. (1954) proposed the theory of Visual field dependence and independence that refers to our perceptual preference type and cognitive style to process environmental information. Based on the results of several studies, the general conclusion is that we better process stimuli information having an independent cognitive style from our visual field because we tend to be more analytical, scan visual images quicker, and are able to build a global image from fragments. On the other hand, if we are dependent on our visual field, we may have a lower capacity to process stimuli, tending to depend on the global image since we perceive it clearer.
Transferring these conclusions to skiing, if we are visual field-dependent skiers we would have the following characteristics:
- We orient visual perception globally and it is more difficult for us to locate parts and distinguish details.
- Take longer to adapt to changes.
- Are prone not to use vestibular and kinesthetic sensations.
- Take longer to respond to certain perturbations since we depend more on the global scene than a local one.
- Tend to fix our gaze to the focus of expansion, even though it serves for linear motions, it disturbs curvilinear trajectories.
- Experience visual search difficulty on environmental changing conditions.
- The distance between our visual fixations (saccadic movements) is smaller.
- We would have a mild form of tunnel vision.
Instead, if we are visual field-independent skiers, our characteristics would be:
- Our visual perception is directed towards the parts, easily locating them by separating environmental details.
- Make use of vestibular and kinesthetic information without interfering with visual information.
- We discriminate better the motion of others approaching.
- Have shorter reaction time with slope signage.
- Have facility at detecting relevant information in complex environments.
- Have a better performance in general.
