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A good control over ocular motility is another basic “visual” ability, which is essential in sports activities.
Ocular movements lead the perception, they move and stabilize the gaze over the object which we are interested in.
To this aim, the ocular motor system have different possibilities of movement at its disposal: saccade (rapid balistic movements), pursuit (the ability to smoothly follow a moving object), vestibulo-ocular reflex, optokinetic reflex and vergence movement (Cervetto & co., 1987).
The gaze stabilization over a target, which is achieved through all the above-mentioned types of movements, is called fixation.
A good fixation results from a proper ocular motility and visual attention, a complex perceptive process which allows us to limit our perceptive field to certain stimuli.
Di Russo and co. (2003) have proved that the fixation stability, as integrated visual-motor ability, is highly superior in elite marksmen than in ordinary people in the presence of peripheral distractions, whereas there is no significant difference in the absence of them.
It seems as if the former were able to ignore peripheral stimuli annoying them, while the latter were more susceptible to being distracted.
In any case, it is not only visual attention that is able to produce advantages in the control over ocular movements, but also other basic motor aspects should be considered.
Indeed, Morrillo and co (2006) have proved that marksmen’s saccadic reaction time is faster than ordinary people’s one, since their saccade motor preparation requires less time.

Edited by Fabrizio Zeri, source: P.O. Professional Optometry, August 2008

Visual input is composed by several abilities, but which are the most important ones for sports action?
Obviously, the function which has attracted the greatest attention within the clinical field is visual acuity, that is a threshold that allows the acknowledgment of high-contrast steady stimuli. It is a very important ability in everyday life, but can it make the difference in sport?
In fact, also from a clinical point of view, visual acuity is deemed a poor indicator of the visual function for many reasons.
First of all, it can be only partially measured. Still today, for the measurement of acuity, we address to the first optic tables, introduced by Snellen and spread by Donders, which can measure the resolution angle up to a minimum of 1′, corresponding to 10/10.
This value, which for a historical error (Calossi, 1992) has been judged the lowest which the human eye could discern (actually, it can reach 0,5 value, that is 30”), has influenced eyecare professionals’ clinical habits from that moment onwards, and is now rooted in common knowledge.
Besides, resolution acuity in sports could be as important as other kinds of spatial acuity, such as detection acuity (minimum dimension of a line or point which could be seen against a homogeneous background), or localization acuity (minimum disalignement among lines which can be spotted).
Whether athletes’ visual acuity is higher than non-athletes’ one is a controversial matter: some critics find this assertion true (Laby e coll, 1996; Jedrusch e coll, 2006), others do not (Christenson e Winkelstein, 1988).
However, several studies report that many athletes achieve a good sports performance in spite of a static (high-contrast) reduced visual acuity (Erickson, 2007; Gregg, 1987).
In any case, static acuity remains an important ability, even as a basis for more complex visual abilities, such as dynamic acuity, which enables to distinguish the details of moving objects.
Of course this ability is really useful in sport, where the visual information to process are rarely still. It is related not only to static acuity, but also to good ocular-motor abilities and other superior functions of integration.
From the ’70s onwards, many studies have highlighted a correlation between the visual dynamic acuity and the sports performance, especially in such sports as volleyball and basketball, or sports where little balls are hit or grasped, such as baseball or tennis (Gregg, 1987, Roncagli, 1990).

Edited by Fabrizio Zeri, source: P.O. Professional Optometry, August 2008

EGOist and EGOistIdea can be personalized also according to the consumers’ different uses and “vision styles”; indeed, there is the possibility of choosing between two different measures for the progressive lenses canals.
The 13mm-canal version is useful to short-sighted people and is the ideal for those who love being outdoor or need a long distance vision.
On the contrary, the EDITOR version (with 10mm canals) is more suitable for those who need a “close preferential approach”, that is those who wear glasses mainly at the desk, for reading, at the computer etc.
Thanks to the Free-Form technology, Optovista can produce EGOist lenses, through just one production series, using different materials: from photochromatic to polarized one, from organic resin to polycarbonate.
As soon as the CustomerCare office receives an EGOist order form (which can be found in the lenses catalogue), the construction process begins; once the data are transferred into the system, the thickness and the inner mapping of progressive lenses are calculated.
The inner surfaces of the EGOist are produced by machines which are capable of cutting the surfaces with a precision of the order of one thousandth millimetre. The perfect correspondence between the prescription parameters and the mathematical pattern developed by the software, guarantees the accomplishment of the curvature.
The two progressive lenses are finally embellished by the magical touch of one of the 3 Top-Coats proposed by Optovista: Encanto Brilliance, Azulux Encanto and Luxial Encanto.

Source: B2eyes Magazine, number 19, November/December 2007

Visual abilities in sports practice.

The visual information is decisive in sports activities. It is through it, together with the other sensitive afferences, that the athlete decides which action he is going to perform, having programmed and checked its accomplishment.
Since vision influences the sports performance, several studies have been trying to find out the critical visual abilities, especially analysing the eventual differences between athletes and non-athletes.
Most of the experts in the field claim that elite athletes can reach higher sports performances thanks to a certain visual superiority (for a review, see Erickson 2007; Gregg, 1987; Roncagli, 1990).
However, the controversial point in literature is the reason for this superiority: on one hand, several outcomes indicate how the visual system of athletes is superior to non-athletes’ one; on the other hand, it seems that the athletes’ visual superiority does not derive from superior visual abilities, but it is rather determined by a more effective use of the visual information at their disposal.
In any case, Erickson (2007) highlights that both aspects are fundamental to a successful performance. In fact, it is not possible even for an expert player, who knows how to make an effective use of the visual information, to achieve good motor results unless he owns at least the basic visual abilities providing visual information (e.g. low sensitivity to contrast or low stereopsis). As well as having two players the same visual ability, greater is the experience and practice in taking advantage of the relevant visual information, better will be the performance.

Edited by Fabrizio Zeri, source: P.O. Professional Optometry, August 2008