The effect of context on the perception of the
letter ‘p’
Abstract
Current literature supports a correlation between the context in which stimuli occurs and our perception of it. It was hypothesised that the context in
which the letter ‘p’ occurs affects the perception of its size and shape. The aim was to replicate research by Diener (1990) on participants who ignore
capitalisation in texting. In the present study, 50 students (24 male and 26 female) aged 16 - 18 were asked to indicate how ‘p’ varied in size and shape
using a 5-point scale. As a control, participants were informed the letters were identical. Participants then made four more comparisons. Despite the
control, participants perceived the size and shape of ‘p’ differently depending on where the vertical line of ‘p’ was placed in the context of the
surrounding letters. The results obtained supported the hypothesis that the “correct” perception of stimuli was influenced by the context.
Introduction
Results
Visual perception involves ‘the selection, organisation and
interpretation of visual sensations into meaningful objects and events’
(Grivas, Down & Carter, 2004, p. 528). The context, or current
setting, in which stimuli is shown may influence how it is perceived.
Grivas, Down and Carter (2004) describe the readiness to perceive
stimuli in accordance with certain expectations as a perceptual set, or
expectancy.
Diener (1990) investigated the influence of context on visual
perception. Diener’s experiment involved participants identifying
whether letter ‘p’ (uppercase or lowercase, separated by another letter)
were identical or different in size. Participants were informed the
letters were identical then asked to repeat the process for another 4
rows of ‘p’ combinations. Diener found that identical letters of the
alphabet tended to be perceived as different in both size and shape,
depending on whether the letters were interpreted as uppercase or
lowercase letters. Diener concluded that context seemed most
influential in shaping an observer’s interpretation of the letter case
when the observed letter was ‘p’.
The aim of this experiment was to replicate the investigation by Diener
(1990) on a generation of participants who frequently ignore
capitalisation of letters when texting or sending SMS messages.
It was hypothesised that Year 12 VCE Psychology students will
perceive the size and shape of the letter ‘p’ differently depending on
surrounding letters, and whether the vertical line in the letter ‘p’ is
perceived as an ascender (above the line) or a descender (below the
line).
The mean score for each row was calculated and recorded in a table.
Method
Participants
Two classes of 50 Year 12 VCE Psychology students from Swinburne
Senior Secondary College between the ages of 16 - 18 were selected
using convenience sampling. 24 were male and 26 were female.
Materials
A printout of Figure 6.53 on page 229 of Grivas, Down and Carter
(2004), a 5-point scale where (1) represented a response that the letters
p were ‘clearly identical’ and (5) ‘clearly different’, pen, and table to
record results.
Procedure
A repeated-measures design was employed.
Informed consent procedures were followed, and confidentiality,
voluntary participation and withdrawal rights explained. Deception
was not used.
Participants were asked to indicate whether the letters ‘p’ in the first
row of Figure 6.53 were identical in size and shape. Reponses were
made on a 5-point scale.
After the responses to the task were collected, participants were told
that the letters ‘p’ were the same size and shape, and that any
difference that appeared was ‘an illusion’.
Participants were then asked to use the size of the illusion for the P&p
figure in Row 1 as a standard control.
The other stimulus pairs in Rows 2-5 were then rated against the
standard in terms of size and the illusion they produced.
Participants were debriefed at the conclusion of the study.
•Table 1: How closely pairs of ‘p’ appear in size and shape
ROW
1
2
3
4
5
MEAN
2
2
5
3
3
1 = clearly identical
5 = clearly different
The mean score for Row 3 indicated participants perceived the two
letter ‘p’ as same in size and shape. The control Row (1) and Rows 2,
4 and 5 indicated participants perceived the letters as different in size
and shape.
The rows were divided into two groups (Group A and Group B).
Group A included Rows 2, 4 and 5, and Group B included Row 2. The
mean score for Group A was lower than the mean score for Group B.
A t-test was conducted to compare the means of the two groups. It was
found that this difference was statistically significant (p<0.05).
Discussion
The results obtained support the hypothesis that the “correct”
perception of the size and shape of the letter ‘p’ is influenced by the
context in which it is shown.
The mean scores showed that when pairs of ‘p’ were perceived as
different in case (uppercase or lowercase) as in Rows 2, 4 and 5, they
were more likely to be perceived as different in size and shape,
compared to when the ‘p’ were perceived as the same case as in Row 3
and therefore same size and shape. A test of significance showed that
the difference between the mean scores of Group A (Rows 2, 4 and 5)
and Group B (Row 3) was statistically significant (p<0.05).
The results obtained were consistent with those gathered by Diener
(1990) who found the majority of participants perceived the ‘p’ as
being uppercase or lowercase depending on whether the vertical line of
the ‘p’ descended below the imaginary horizontal line upon which all
the letters sat or remained above.
A limitation of this study was that participants were Year 12 VCE
Psychology students and may have been familiar with perceptual set.
This impacted on the study because the participants may have paid
more attention to the context of the letter ‘p’ than participants who
were not studying perceptual set. This could be avoided in the future
by staging the experiment prior to the commencement of studying
perceptual set.
Despite these limitations and the relatively small sample size, the t-test
indicated the difference between Rows 2, 4, 5 and Row 5 was
statistically significant and therefore the results could be generalised to
the research population.
Reference List
Diener, D. (1990). The P&p illusion. Perception and Psychophysics,
47(1), 65-67.
Grivas, J., Down, R. & Carter, L. (2004). Visual Perception (pp. 171256), Psychology: VCE Units 3 & 4 (3rd Ed.). South Yarra, VIC:
Macmillan Education Australia Pty Ltd