Our ocular capabilities while skiing are employed to execute specific actions with our eyes. They can be developed and improved if we first are conscious of them by visual training, also called sports vision.
Binocular disparity is the difference in the image location of an object seen by our right and our left eye due to pupils’ separation. It is used to determine depth and terrain relief.
Visual acuity is applied to detect specific objects’ details, terrain changes, and snow. The dynamic visual acuity is an important skill while skiing at a higher speed and the faster, the more it is needed.
Peripheral vision consents us a wide visual field control while foveal or central vision allows greater visual acuity.
Depth perception is the capacity to distinguish the distance between objects in the foreground and the background. It helps us to process visual information during visual anticipation, being essential for skiing in the forest, on a mogul field or a slalom course.
Saccades are quick and precise eye movements, like glances or glimpses, from one point to another that facilitate our peripheral visual field exploration. They occur because of an external stimulus (an object or a person appears in our visual peripheral space) or because of our will. As we need to bring the information perceived through the peripheral vision to the fovea, our eyes are in constant movement. These movements serve to guide our visuospatial memory and attention, since moving from one eye fixation to another, the space detected in the previous fixation is remembered. The reason we are constantly implementing saccades is that the fovea (the central part of the eyes) is an area of great visual acuity but with very limited amplitude, and this is why we need to move our eyes for information pickup across the visual field, especially within wide surroundings.
Smooth pursuit is the ability to smoothly accompany a moving target or a stationary object while we move. It is used to follow the instructor’s technical demonstration or other skiers in motion, helping stabilize our eyes during head rotations. Saccades are fast in terms of our eyes’ position change while smooth pursuit movements are gradual and continuous. Both movements are swapped during our visual detection process.
Ocular fixation is the ability to keep our eyes fixed to a certain point of the visual scene, under stable visual attention, for information pickup without distractions. Inspection time is the time that our gaze fixation takes to a target. Certain parts of the visual scene receive more fixation time because it helps determine our future actions. If visual inspection time is too short then we may fail to determine the situation’s insight, and if it is too long, our perception may dissipate. In skiing, our visual fixation is used to guide motion towards a determined direction, avoid obstacles, calculate the approach and/or braking to an object or a static or in motion person.
The focusing speed is our capacity to change visual focus from close to far areas or vice-versa. The slow implementation pace of this ability delays decision-making. This skill is more important when motion speed increases.
Vergence movements are smooth and gentle antagonist movements of both eyes to regulate our gaze for different distances. Converging movements (convergence) are applied to near objects targeting when our eyes rotate towards the center, while focusing a remote one it is used divergent movements (divergence) where the eyes rotate returning to their normal parallel state.
The accommodation movements are related directly with vergence movements to regulate our gaze in distance, making eye muscles adjusting the contour of the lens to focus the image on the retina.
The pattern recognition is our ability to identify repeated patterns of the terrain configuration, its contour, and inclination.
Visual discrimination is the capacity to recognize differences and similarities between shapes, colors, measurements, etc.
Our dominant eye is the first eye that processes and sends visual information to our brain, guiding also the other eye fixations. This eye dominates vision because of greater visual acuity.
Contrast sensitivity is the ability of our visual system to discriminate light differences between contiguous areas as, for example,distinguish an object from its background, different shades of snow’s white, and light or shadowed areas of a slope.
The blinking function is to protect the surface of the cornea by keeping it clean and lubricated. It is estimated that blinking consumes 5% of effective vision. Stern & Dunham (1990), distinguished three types: reflex blink occurs as an automatic reaction to an external stimulus, spontaneous blink as an involuntary action, and voluntary blink. External factors such as temperature, humidity, and air flow affect blinking but also internal factors such as our mental and emotional state. It decreases while increasing attentional load and increases in anxiety or nervousness conditions. We control our blinking to lose the least amount of visual information as possible or when we look at something important (Nakano et al. 2009, Shultz et al. 2011).
Attentional blink is the difficulty of recognizing a second immediate stimulus after identifying the first one. It happens when we blink continuously and do not reach the detection of successive stimuli losing selective attention, which is equivalent to having a “blind moment”.
The visual field is the spatial amplitude that our eyes can see, or, in other words, our visual extension without eye movements. In skiing, the field of view should be as broad as possible and gaze fixation should not aim exclusively at a fixed point. Thanks to practice, the expert’s visual field is broader since he uses both central and peripheral vision; instead, the beginner skier employs mostly central vision. While intensifying the slope or the situation complexity, our peripheral vision decreases while increasing central vision, so we maintain gaze toward the complex points of the slope.
Saccadic suppression is the moment in which there is a significant reduction of visual sensitivity. To cover the distance between visual fixations, our eyes utilize saccades. Between fixations, they do not detect the visual scene completely but in a fuzzy way in which they are momentarily “switched off”, discontinuing detecting the visual scene until they return to gaze fixation again.
According to these considerations, you can apply the following recommendations in your own skiing:
- Remember that if your visual inspection time is too short, then you may fail to determine the situation’s insight, and if it is too long, your perception may dissipate.
- Increase your central vision skill while skiing at higher speeds and the faster, the more you will need it.
- In slope congestions, applying peripheral vision is more appropriate.
- The faster you ski, the more you will have to extend your gaze towards the direction of descent.
- Avoid gaze fixating exclusively at a fixed point, instead, try to broaden your visual field using both central and peripheral vision.
