Robert M. Duncan
J. Allan Cheyne
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• Private speech: vocalized speech not addressed to anyone but the speaker
• Vygotsky:
– Private speech is a form of thinking, problem -solving, and self -regulation.
– Children use private speech from ages 3-8 before speech is internalized.
• Private speech has been studied almost exclusively in children.
• What about adults?
2
• Rates of private speech increase as children get to more difficult parts of a task (Vygotsky , 1996).
• Among children (Vygotsky , 1978; Duncan & Pratt; 1997):
– First: action
à speech
– Then: speech
à action
• Compared with external speech, internal speech is disconnected and incomplete—predication (Vygotsky ,
1934).
– Example from Thought & Language
– Commonly, the subject is omitted while the predicate is used.
– Private speech among children working on tasks tends to be abbreviated or fragmented ( Goudena, 1992; Pellegrini , 1981;
Azmitia, 1992; Feigenbaum, 1992).
3
• To determine whether adults use more private speech when working on difficult compared to easy tasks.
• To explore the location of adults’ private speech in relation to their actions.
• To examine psychological predication in adults.
4
• Participants
– 27 male & 26 female undergrads
• Procedure
– 2 sessions with each participant
– Each session (counterbalanced):
• Easy computer task (1) -- kilobytes
• Difficult computer task (2) -- kilobytes
• Paper-folding task (3) – 0, 1, 2
5
• There was a main effect of task on utterances per minute; F (2, 104) =
13.84, p = .00).
3.5
2.5
3
2
1.5
1
0.5
0
RATE
Diff 1
Diff 2
Easy
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• There was also an interaction of session x task on speech proceeding action ; F (2,
86) = 5.96, p < .01.
– Simple main effect for task was significant for only session 1, F (2, 86) = 12.94; p < .001.
– Percentage of speech proceeding action was higher on second trial on difficult task than first trial, t (43) = 4.97, p < .001.
7
25
• There was a main effect of session on psychological 20 predication, F (1, 43)
= 5.60, p < .05.
15
Session 1
Session 2
10
5
8
0
% predicative speech
• There was a main 1.8
effect of trial on rate
1.6
of speech; F (2, 104)
1.4
= 40.29, p < .001.
1.2
1
0.8
0.6
0.4
0.2
0
Rate
Trial 1
Trial 2
Trial 3
9
• There was a main effect of trial on
20
18 percentage of speech
16 proceeding action; F
14
(2, 52) = 7.62, p <
12
.01.
10
8
6
4
2
0
% speech proceeding action
Trial 1
Trial 2
Trial 3
10
• Every participant used private speech while being observed, and about half the children in a sample usually use private speech (Berk , 1992; Diaz, 1992).
• Young adults’ private speech was manipulated in ways that are used to manipulate the private speech of children.
• Private speech may have many of the same functions across ages.
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• Short-term change in self-verbalization was evident.
• Rate of speech decreased across trials on difficult computer tasks and paper-folding tasks.
• Percentage of speech preceding action increased across trials (only session 1 in computer task).
• Relative amount of psychological predication increased across sessions.
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• Sort of…
– His ideas about task difficulty, self-regulation, and psychological predication in relation to private speech were right…and
– Private speech does appear to be a form of thinking and problem solving.
• But…
– Private speech seems to be more than just a phase of development.
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