TESTING THE OCULAR DOMINANCE OF INFANTS By Norma V. Scheidemann University College, University of Southern California and Gladys E. Robinette Director and Teacher
of Child Development, Pasadena, California
John Muir
Pre-School,
The normal individual by nature is either right or left-sided. One side of the body seems to be used in preference to the other in regard to hand, eye, foot, so that the individual is dextro-expert The native dominance is he or sinistro-expert.1 so and on, ear, nose, of one of these factors may, then, be considered an index to the native sidedness of an individual. Of these various factors, native eyedness is the one most readily discoverable and the most reliable, since it is not affected by training. Handedness often is influenced extraneous conditions and is
subject to training hence cannot index of native sidedness. The discovery of the dominance of other factors entails too much labor to be practical. Clinical diagnosis often requires the determination of an individual's native sidedness, and at present the simplest way of by
be taken
as an
this is to determine ocular dominance. Several commercial tests for ocular dominance are on the market, but the paperhole test is much simpler and is wholly satisfactory since it com-
determining
the commercial tests. This test is sheet of paper in which a small hole (about onehalf inch in diameter) is cut. The paper is held about fifteen or twenty inches from the eyes of the subject, and the subject is required to look through the hole at a small object about twelve inches
prises
the
no more
principles underlying
than
a
opposite side of the hole. When the subject has fixated the small object the subject's head and the paper are held steady while the subject's right eye is covered. If the subject then fails to see the small object, he is right-eyed; if he still sees the object, he is left-eyed. With a little practice the experimenter will be able to observe which eye the subject uses in fixating the object. When the writers found this test wholly satisfactory in testing on
the
1
Gould,
G.
Company, 1908,
M., Right-Handedness
and
pp. 18-20. G2
Left-Handedness,
J. B. Lippincott
OCULAR DOMINANCE OF INFANTS
63 whether it
kindergarten and pre-school children, they wondered would be possible to discover the eyedness of infants. After some experimentation a satisfactory method of procedure was developed that seemed to be satisfactory for infant testing. A large cardboard with a small hole in it was first placed in the child s hands. Usually he proceeded to stick a finger through the hole. The experimenter then took the cardboard and tried
to induce the child
Where s the play "peek-a-boo" through block ?'' while holding a brightly colored block at some distance in back of the hole. In some cases the child's attention was attracted the hole
to
or
asked
initiated by projecting a pencil through the hole and then withdrawing it slowly while the child watched it. A small pocket flashlight proved to be the best stimulus and was especially satisfactory in a dimly lighted room. A rattle was used for variety when there was difficulty in obtaining the
to the hole and
cooperation
was
child's attention. When the child succeeded in fixating the object behind the hole it was possible to observe which eye he used from the position in which he held his head. This general procedure first was carried out with a child twentynine months of age. Attempts on two days were unsuccessful, but the child's fixed attention and prolonged gaze through the hole that permitted the use of only one eye was taken to indicate that the light was fixated. In this case the child used his right eye. At varying intervals nine more trials were made; in each the child used his eye. on
the third
day
right
Work with a twenty-seven months old child proved successful after the attempts on two preceding days were unsuccessful. In this case the child used her left eye. Repeated trials on three succeeding days found this child always used her left eye. She also reached for the with her left hand, and tried to brush the card
light
away with her left hand. When the mother was informed of this, she said that the child eats with her left hand and shows preference for it in many ways. Efforts with infants twenty-four, twenty-three, and twenty-one months of age respectively proved to be successful, but no results were obtained with infants sixteen, twelve, and six months of age. At what particular age it is possible to obtain a child s attention but unso that this experiment may be successful is not known, The work children. with individual the would
doubtedly
age
vary
shows that ocular dominance can be tested at a much earlier age than commonly is supposed to be possible. This fact may be found to have practical implications.
in this
study
of Child Development, Pasadena, California
John Muir
Pre-School,
The normal individual by nature is either right or left-sided. One side of the body seems to be used in preference to the other in regard to hand, eye, foot, so that the individual is dextro-expert The native dominance is he or sinistro-expert.1 so and on, ear, nose, of one of these factors may, then, be considered an index to the native sidedness of an individual. Of these various factors, native eyedness is the one most readily discoverable and the most reliable, since it is not affected by training. Handedness often is influenced extraneous conditions and is
subject to training hence cannot index of native sidedness. The discovery of the dominance of other factors entails too much labor to be practical. Clinical diagnosis often requires the determination of an individual's native sidedness, and at present the simplest way of by
be taken
as an
this is to determine ocular dominance. Several commercial tests for ocular dominance are on the market, but the paperhole test is much simpler and is wholly satisfactory since it com-
determining
the commercial tests. This test is sheet of paper in which a small hole (about onehalf inch in diameter) is cut. The paper is held about fifteen or twenty inches from the eyes of the subject, and the subject is required to look through the hole at a small object about twelve inches
prises
the
no more
principles underlying
than
a
opposite side of the hole. When the subject has fixated the small object the subject's head and the paper are held steady while the subject's right eye is covered. If the subject then fails to see the small object, he is right-eyed; if he still sees the object, he is left-eyed. With a little practice the experimenter will be able to observe which eye the subject uses in fixating the object. When the writers found this test wholly satisfactory in testing on
the
1
Gould,
G.
Company, 1908,
M., Right-Handedness
and
pp. 18-20. G2
Left-Handedness,
J. B. Lippincott
OCULAR DOMINANCE OF INFANTS
63 whether it
kindergarten and pre-school children, they wondered would be possible to discover the eyedness of infants. After some experimentation a satisfactory method of procedure was developed that seemed to be satisfactory for infant testing. A large cardboard with a small hole in it was first placed in the child s hands. Usually he proceeded to stick a finger through the hole. The experimenter then took the cardboard and tried
to induce the child
Where s the play "peek-a-boo" through block ?'' while holding a brightly colored block at some distance in back of the hole. In some cases the child's attention was attracted the hole
to
or
asked
initiated by projecting a pencil through the hole and then withdrawing it slowly while the child watched it. A small pocket flashlight proved to be the best stimulus and was especially satisfactory in a dimly lighted room. A rattle was used for variety when there was difficulty in obtaining the
to the hole and
cooperation
was
child's attention. When the child succeeded in fixating the object behind the hole it was possible to observe which eye he used from the position in which he held his head. This general procedure first was carried out with a child twentynine months of age. Attempts on two days were unsuccessful, but the child's fixed attention and prolonged gaze through the hole that permitted the use of only one eye was taken to indicate that the light was fixated. In this case the child used his right eye. At varying intervals nine more trials were made; in each the child used his eye. on
the third
day
right
Work with a twenty-seven months old child proved successful after the attempts on two preceding days were unsuccessful. In this case the child used her left eye. Repeated trials on three succeeding days found this child always used her left eye. She also reached for the with her left hand, and tried to brush the card
light
away with her left hand. When the mother was informed of this, she said that the child eats with her left hand and shows preference for it in many ways. Efforts with infants twenty-four, twenty-three, and twenty-one months of age respectively proved to be successful, but no results were obtained with infants sixteen, twelve, and six months of age. At what particular age it is possible to obtain a child s attention but unso that this experiment may be successful is not known, The work children. with individual the would
doubtedly
age
vary
shows that ocular dominance can be tested at a much earlier age than commonly is supposed to be possible. This fact may be found to have practical implications.
in this
study
