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Wednesday, October 13, 2010

Exercise X - Visual Sequential Processing or "Eyes out of Orbit"



According to the PTS II manual, Visual Sequential Processing develops the ability to identify and count a specific stimulus that is repeated in a sequence of different stimuli. Visual Sequential Processing requires Temporal Visual Processing, Perceptual Speed, Visual Attention, Visual Concentration and Saccadic Fixation.

You have to count the number of times a specified stimulus appears in sequence of stimuli. The target flashes inside of a box and then a series of letters, numbers or pictures will be flashed on the screen.

Variables:

There are four types of stimuli: Pictures(very difficult because they are somehow stylized and not very clear), Upper Case Letters, Lower Case Letters, Numbers
Stimuli Size: Medium and Large.
Speed of Stimuli: there are seven speeds ranging from slow to fast.
Number of Stimuli: it varies from 20 to 60 stimuli.
Stimuli Placement Patterns: there are six progressive placement patterns utilized.

The patterns could have a fixed or a random presentation.
In the fixed presentation, the stimuli will be presented in a fixed order and location. In the random presentation, the location of the stimuli in the sequence within a level will be randomized: it could show up on random places on the screen.
At this point, the speed is very fast. Hold on to your eye balls her or they go out of the orbit :o

It improves concentration, attention and saccadic fixation and speed. Good exercise for fast music.

Tuesday, October 5, 2010

Eye-Hand/Voice Span and Perceptual Span

Eye-Hand/Voice Span: measures how far ahead the eyes are from the hand/voice

Skilled readers Less skilled readers

4 notes 2 notes (Furneaux and Land)
about 2 beats under one beat (Truit at al.)
2 beats 0.5 beat (Rayner and Pollatsek)
1-2 notes 1-2 notes (Weaver) (more complex music)
4 beats (singers- Goolsby, 1994)
0 up to 2 notes (Jacobsen, 1941)


(I think it is more effective to measure EHS in beats because of the “chunking” abilities of the musicians-one beat can include several notes).

All researchers agree that the EHS of the musicians is small.
Truitt at al conclude that musicians do not need to see more then one measure ahead of the hands/voice in order to read well and readers rarely extract information beyond a measure (4 beats). However small, that does not mean that the visual process of the music is not ahead of the fixation (Weaver, 1943; Goolsby, 1994; Kinsler and Carpenter, 1995).
Rayner and Pollatsek state: “This discrepancy between the data and conventional wisdom might be due to the fact that musicians, like all human perceivers, are seduced by the illusion that information can be extracted from a wider region of vision than is actually possible”. (1997)


Perceptual Span: it measures the size of the visual field and our awareness of it. The perceptual span is the region around the fixation in which we obtain some information.

Both Truit at al and Rayner and Pollatsek (1997) found that, contrary to the musicians believes, the perceptual span is also small (the visual processing is also close to the hands). Its size is more or less one measure. That is > 2 < 4 notes ahead of the hands. Visual processing for musicians is also comparable to reading aloud (1.1 words for adults and less then half a word for a 1st grader-Garzia) and typing (about 6 characters-Rayner and Pollatsek).
(When researchers measure the EHS, they are taking the average and when they measure the perceptual span, they take the maximum).


Rayner and Pollatsek concluded that the less skilled reader when combining the EHS and the PS, extract useful information up to about 3 or 4 beats ahead of the hands. For skilled readers, the combination leads to only up to 5 beats ahead of the hands.

In the article Eye Movements in Reading: Facts and Fallacies by Stanford E. Taylor, he estates that “No studies to date have shown that training to widen span has resulted in the ability to see in phrases during continuous reading. Feinberg’s study (1949) suggested that the physiological limitations of the eye will probably present readers from ever reaching this goal “… when retinal impressions are superimposed on preceding ones at the rate of 3 to 5 per second in a dynamic act where the kinesthesia of the ocular activity and the sequence of impressions further reduce the already rather tenuous peripheral impressions. In addition, there is the demand for continually organizing the multiple ideas presented in reading material. Consequently, the span of recognition in reading is distinctly smaller than that occurring and measured in static seeing situations (Taylor, 1957) and maybe thought of as “salvageable” span”.