1. +
The Development of the SNARC Effect
in 5- to 9-Year-Old Children
Claire Lenehan

2. +
The SNARC Effect

Spatial-Numerical Association of Response Codes

Humans have an internal spatial representation of
numbers

Numbers are associated with left-right coordinates

Dependent on cultural and experiential factors

3. +
Discovery of the SNARC Effect

First discovered by Dehaene et al. (1990, 1993)

Detected through a parity judgment task

Response times are faster on the left for small numbers and
the right for larger numbers

Magnitude is not necessary for deciding parity, but numerical
magnitude is activated automatically

4. Even
Odd
2

5. Even
Odd
1

6. Odd
Even
8

7. Odd
Even
9

8. +
The SNARC Effect in Children

The SNARC effect has been found in American children as
early as Grade 3

The effect increases with age (Berch et al., 1999)

Chinese kindergarteners children display the SNARC effect
(Yang et al., 2013)

These studies have employed parity tasks, which require
automatic numerical magnitude activation

9. +
Van Galen and Reitsma

Employed two different tasks to investigate the presence of the
SNARC effect in 7-, 8- and 9-year-old children

Gray box detection task

Magnitude judgment task

Found that 9-year-old children displayed the SNARC effect on
both tasks

7- and 8-year-old children displayed the SNARC effect only on
the magnitude judgment task

10. +
Current Study

Adaptation of van Galen and Reitsma’s magnitude task

Goals

To determine whether the SNARC effect is present before age 7

To compare the strength of the SNARC effect at different ages

Van Galen and Reitsma did not test children under age 7, but
suggested that the SNARC effect would be present as soon as
children had mastered the meaning of Arabic numerals

It is expected that all participants will display the SNARC
effect, and that the effect will be stronger in older children

11. +
Participants

Four participants

Participant 1


Participant 2


Male, Age 6 years
Participant 3


Male, Age 5 years 10 months
Male, Age 9 years 2 months
Participant 4

Male, Age 9 years 4 months

12. +
Procedure

Children were tested individually in their homes

Participants were instructed that, for the purpose of this
experiment, numbers smaller than 5 were “small numbers” and
numbers greater than 5 were “big numbers”

Flashcards were used to ensure that all participants understood
which numbers belonged to which group

Instructions were given orally, then children completed the
magnitude task on a laptop computer

13. +
Magnitude Task

PsychoPy software was used to create a magnitude task

Stimuli were the Arabic numerals 1, 2, 3, 4, 6, 7, 8, 9

Participants responded to whether numbers were “Big” or
“Small” by pressing designated response keys

The left key was blue and the right key was yellow

There were two blocks of trials, each consisting of 24 or 40
trials preceded by 8 practice trials

14. +
Magnitude Task

Block A

Congruent task



“Small” appeared on the left side of the screen in blue
“Big” appeared on the right side of the screen in yellow
Block B

Incongruent task



“Big” appeared on the left side of the screen in blue
“Small” appeared on the the right side of the screen in yellow
Two participants completed Block A first and two started with
Block B

19. +
Results
Average Response Time (seconds)
Block A
Block B
Difference
Participant 1
1.1847
1.3362
0.1514
Participant 2
0.9739
1.0583
0.0844
Participant 3
1.0063
1.1774
0.1711
Participant 4
0.9994
1.1669
0.1675

20. +
Statistics

A paired two-sample t-test was used to compare the response
times in Block A vs. Block B

t = 5.1682, p < .05

An unpaired two-sample t-test was used to compare the results
of the 9-year-olds with those of the 5- and 6-year-olds

t = 1.5321, p > .05

21. +
Conclusions

The participants displayed the SNARC effect

Age did not play a significant role in the strength of the effect

22. +
Limitations

The small number of participants makes it difficult to compare
children of different ages

The limited number of trials makes it impossible to analyze the
results for individual numbers

No gender differences have been found between adults, but
there could be differences between boys and girls

The participants may not be representative of the general
population

23. +
Questions?