Nasal Visual Field

Flicker RateNo Flicker 3 Hz 10 Hz

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rees

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3 Months 7 MonthsAdults

Temporal Visual Field

Flicker RateNo Flicker 3 Hz 10 Hz

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1007 MonthsAdult

3 Months

Suppression Task. We used a task modeled on Gernsbacher et. al. (1991)

Lewis and colleagues 3,4 measured the monocular visual field extent of 3-, 4-, and 6-month-old infants using 6-Hz flickering or non-flickering lights. The results showed larger measured visual field extent for flickering stimuli than for non-flickering stimuli in 3- and 6-month-old infants in the temporal visual field, but not in the nasal visual field. No effect of flicker was reported for 4-month-old infants in either the temporal or nasal visual field.

The Role of Suppression in

Jason Barker, Lea Hald & Janet Nicol Department of Psychology - University of Arizona - Tucson, Arizona

Methods

References

Results

Acknowledgements

Procedure.

• Subjects were positioned with their eyes 36 cm fromthe central fixation stimulus which was extinguished once the peripheral target was illuminated.

•The fixation stimulus, located at the intersection of thefour perimeter arms, consisted of a 6-diameter ring of eight yellow 0.6 LEDs.

• An observer, hidden behind a black curtain reported the child’s eye movements.

• Adults were instructed to fixate the central stimulus, and then identify the location of the peripheral stimulus.

• Each subject was tested with sixteen trials, one trialat each of four locations on each of the four perimeter arms.

• One-third were tested with a 3-Hz flickering stimulus.

• One-third were tested with a 10-Hz flickering stimulus.

• One-third were tested with a non-flickering stimulus.

ConclusionsIntroduction

Temporal visual field analysis. In the temporal direction, measured visual field extent in infants was significantly smaller (p<0.05) for the non-flickering stimuli than for both the 3 Hz and 10 Hz flickering stimuli. Temporal visual field extent did not differ between the 3 Hz and 10 Hz flickering stimuli. Stimulus flicker did not affect measured visual field extent in adults.

Subjects. Subjects were 24 University of Arizona undergraduates who received course credit for participation. All were native speakers of English.

Inhibitory processes play a central role in many current models of language and memory. Gernsbacher and colleagues (see Gernsbacher & Faust, 1995 for a review) have conducted a number of studies specifically investigating the importance of inhibiting or “suppressing” irrelevant information during the course of language processing. Using a simple semantic interference task to assess suppression skill, they have demonstrated that this ability is related to overall comprehension skill, successful inhibition of incorrect forms of homophones, and quickly identifying the correct target of anaphoric reference. They have also found relationships with non-linguistic tasks, such as the tendency to report typical, but absent, objects from visual scenes.

arms that extend to 110 along the 45, 135, 225, and 315 half-meridia. Yellow, 3°-diameter, flickering or non-flickering LED stimuli were used.

Nasal visual field analysis. In the nasal direction, measured visual field extent in infants was significantly smaller (p<0.05) for the non-flickering stimuli than for the 10 Hz, but not the 3 Hz flickering stimuli. Nasal visual field extent did not differ for 3 Hz and 10 Hz stimuli. Stimulus flicker did not affect measured visual field extent in adults.

1. Bock & Miller (1991) Broken Agreement. Cognitive Psychology, 23, 45-93.

2. Eberhard, K.M. (1997). The Marked-Effect of Number on Subject-Verb Agreement. Journal of Memory and

Language, 36, 147-164.3. Gernsbacher, M.A., & Faust, M. (1991). The mech-

anism of suppression: a component of general comprehension skill. Journal of Experimental Psychology: LMC, 17, 245-262.

4. Nicol, J.L., Forster, K.I., & Veres, C. (1997). Subject-verb agreement processes in comprehension.

Journal of Memory and Language, 36, 569-587.

This work was supported in part by National Multipurpose Research and Training Center Grant #DC-01409 from the National Institute on Deafness and Other Communication Disorders, and by the Cognitive Science Program and Dept. of Psychology at the University of Arizona.

Peripheral stimulus flicker enhanced measured visual

field extent for both the 3.5- and 7-month-old infants

when a 10 Hz flicker rate was used. However, when a

3 Hz flicker rate was used, an effect of flicker was

found only in the temporal direction and not in the

nasal direction. We found no effect of flicker in the

adult subjects.

Tasks

Flicker rate

3 Hz 10 Hz

Nasal Temporal Nasal Temporal

3 Months No Yes Yes Yes

7 Months No Yes Yes Yes

Adult No No No No

Do flickering stimuli result in significantly larger measured visual field extent?

Apparatus. The apparatus was a black double-arc perimeter, with 3.5-cm-wide

-200

-100

0

100

200

300

400

-100 -50 0 50 100 150 200 250

Interference on Suppression Task (ms)

Inte

rfe

ren

ce

on

Ag

ree

me

nt

Ta

sk

(m

s)

Efficient Suppressors

Inefficient Suppressors

Totals

100 ms Delay 1000 ms Delay

Average Interference (ms) at

101.1 51.7

86.34

115.86

-9.38

112.73

-20

0

20

40

60

80

100

120

140

100 ms Delay 1000 ms Delay

Relative Interference at

(ms

)

Efficient Suppressors

Inefficient Suppressors

2175

2225

2275

2325

2375

2425

ss sp pp ps

Sentence Type

RT

(m

s)

Efficient Suppressors

Inefficient Suppressors