本文內容，來自Optometric Management of Learning Related Vision Problems 2nd Edition
Mitchell Scheiman OD (Author), Michael W. Rouse OD MS FAAO (Author)
譯者：量子云圖翻譯組
▲ 來源 | www.aoa.org
Oculomotor眼球運動
A clinical evaluation of the oculomotor system usually assesses three types of eye movements: fixation, pursuits, and saccades. Eye movements are essential for effective visual processing.24 For example, the saccadic system shifts the fovea to an area of interest so that detailed information can be processed. Another example of the importance of eye movements for visual processing is reading, in which the individual will make a series of small saccades and short fixation pauses. Investigation of the dynamics of oculomotor skills (e.g., latency) has focused on the infant, and less research has been done to evaluate preschool and school-age children. Investigation of oculomotor skills in school-age children has centered on eye-movement patterns during reading.
眼球運動系統的臨床評估，通常涉及三種眼球運動：注視、追蹤和掃視。眼球運動是有效的視覺處理的基礎。[24]例如，掃視系統將中央凹移到感興趣的區域，以便處理詳細的信息。眼球運動對視覺處理重要性的另一個例子是閱讀，在閱讀時，個體會做一系列的小掃視和短暫的注視暫停。對眼球運動的動力學（如潛伏期）的研究，主要集中在嬰兒身上，對學齡前和學齡期兒童的評估研究較少。學齡兒童眼動技能的研究，主要集中在閱讀過程中的眼動模式。
Fixations.The newborn's foveal immaturity and poor visual acuity indicate that fixations may be poorer during the first 2 to 3 months of life than during adulthood.25 The central retinal region is probably equally sensitive over a 5-degree area during the first 2 months of lifes3; as a result, a specific central site where fixation preference would be advantageous may not exist during this period. Direct evidence of this supposition is not available because of the uncertainty of measuring the Kappa angle early in life. Newborns, however, will steadily fixate on an object and infrequently shift fixation to another object. The tendency to fixate on new objects increase during the first 3 months of life.26
注視。新生兒的中心凹不成熟，並且視力低下，這表明在出生後的前2至3個月內，他們的注視能力比成年期差。[25]在出生後的頭2個月，視網膜中央區域在5度範圍內，可能同樣敏感[3]；因此，在此期間不存在注視偏好優先的特定中心部位。由於在生命早期，Kappa角測量的不確定性，因此無法獲得這種假設的直接證據。然而，新生兒會穩定地注視一個物體，很少會將注視轉移到另一個物體上。在出生後的前3個月，對新物體的注視傾向增加。[26]
Pursuit Eye Movements.Pursuit eye movements enable continuous clear vision of moving objects within a stable visual environment.27 These eye movements would appear to be susceptible to postnatal foveal development and the corresponding reduction in visual acuity.27 This may account for the finding that infants under 8 weeks of age do not show smooth pursuit eye movements when tracking pendular target motion at varying velocities.27,28 Instead, tracking responses consist of saccades, which act to allow the eye to catch up to the moving target. At 2 to 3 months of age, the infant is capable of generating a smooth pursuit eye movement to track a moving target. The eye movements, however, are still not adult-like, and fixation tends to lag behind the target.27,28 There is evidence that pursuit eye movements continue to improve during childhood.29-32 For example, children tend to wait longer than adults to change direction when tracking a target with a predictable path.24,30
追隨。追隨眼球運動，讓我們能夠在穩定的視覺環境中，連續清晰地看到運動中的物體。[27]這些眼球運動，似乎容易受到出生後中心凹發育水平和相應的視力下降的影響。[27]這可能解釋了以下發現:8周以下的嬰兒，觀察以不同速度擺動的目標時，並沒有表現出平滑的追隨眼球運動。[27]，[28]相反，追蹤反應包含掃視，掃視的作用是讓眼睛趕上運動的目標。在2到3個月大的時候，嬰兒能夠產生一個平滑的眼球追隨運動，追蹤移動中的目標。然而，他們的眼球運動，仍然不同於成年人，注視往往落後於目標。[27],[28]有證據表明，在兒童時期，追隨運動繼續得到改善。[29]-[32]例如，當跟蹤具體可預測路徑的目標時，兒童傾向於比成年人等待更長的時間，才能改變視線方向。[24],[30]
▲來源 | www.slideshare.net
眼球運動的發育：從出生開始持續發育：前庭眼反射，視動性眼顫；從出生開始持續發育：掃視；從出生後6-8個月開始吃席發育：追隨；從出生後3個月開始持續發育：聚散、調節、雙眼視。
Saccadic Eye Movements.Saccadic eye movements are rapid shifts in fixation from one part of the visual field to another in order to place a new image on the fovea. These eye movements are easily observed in newborns but tend to be infrequent. During the first 3 months of life, the frequency of changing fixation to new visual objects increases.26 Accurate saccades depend on coordinating the locus of retinal stimulation with a neuromotor command.33 That is, a peripheral target at 10 degrees should result in a saccade of approximately the same amount. At 1 to 2 months of life, the infant has difficulty generating an accurate saccade: he or she will change fixation to a new target with a series of small saccades that rarely exceed 50% of the target distance.26,34 The saccades are in the right direction but are grossly hypometric. There is a systematic improvement during infancy, with a decrease in the number of saccades needed to reach the target and an increase in the amplitude of the primary saccade.34 By 7 months of age, the hypometric responses are reduced, but accuracy is still not adult-like.34
掃視。掃視眼球運動，是為了在中央凹上放置新的圖像，而將注視從視野的一部分，迅速轉移到另一部分。這些眼動在新生兒中很容易觀察到，但往往不常見。在生命的前3個月，改變注視到新視覺對象的頻率增加。[26]精確的掃視，取決於將視網膜刺激的位置，與神經運動命令協調一致。[33]也就是說，在周邊10度的目標，應該產生大致相同數量的掃視。嬰兒在1到2個月大時，很難產生準確的掃視：他或她將使用一系列很少超過目標距離50％的小掃視，將注視點調整到新的目標上。[26],[34]掃視的方向是正確的，但通常幅度較小。嬰兒期有一個系統性的改善，達到目標所需的掃視次數減少，原發性掃視幅度增加。[34]到7個月大時，小幅度的掃視反應降低，但準確度仍低於成人。
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