2011. Vol.2, No.6, 624-630
Copyright © 2011 SciRes. DOI:10.4236/psych.2011.26095
Inner Speech, Active Part of Working Memory Phonological
Loop, Inactive in Dementia
Maryam Atabati1*, Nader Jahangiri1, Naghmeh Mokhber2
1Department of Linguistics, Ferdowsi University of Mashhad, Mashhad, Iran;
2Psychiatry and Behavioral Sciences Research Center of Mashhad University of
Medical Sciences, Mashhad, Iran.
Received June 1st, 2011; revised July 17th, 2011; accepted August 26th, 2011.
This paper examines the role of inner speech in storage and retrieval of working memory phonological loop by
conducting maintenance rehearsal test on eighteen elderly participants in two groups: a healthy group and a
group with dementia. A Mann-Whitney U test was used to analyze the data. Through a comparison of the re-
hearsal manner of the two groups, it was concluded that the pattern of normal rehearsal of the healthy group was
different from the pattern of patients suffering from dementia: also, the activity of working memory phonologi-
cal loop in the healthy group was different from the lack of activity of working memory phonological loop in
patients. That is, that subjects with dementia cannot use inner speech in the form of subvocal repetition was ex-
plained by applying the “Baddeley and Hitch” model of memory.
Keywords: Inner Speech, Maintenance Rehearsal, Phonological Loop, Dementia
To memorize something, one should either establish seman-
tic relationships between that thing and the experiences that
exist in their mind and expand their mental connection network
or commit it to memory by repetition. In all of these stages,
language on its own is active. Whether when we are trying in
finding the actual or artificial relation of new events with past
events or when we embark on repeating to achieve mental
maintenance, it seems that the role of language is examinable
between childhood amnesia and old age amnesia. Because ma-
jor cases of deficiency and weakness of memory forces are
being manifested in old age and also because the rehearsal and
self-directed speech are having the role of memory sign main-
tenance, the study of the nature of self-directed speech in old
age in two groups of healthy subjects and patients could be
illustrative of the difficulties related to the decline of verbal
memory in old age. Because in “free recall” memory, mental
processes have not been dealt with and only the output has been
at the center of attention, the need for a close analysis of the
processes going on with the subjects ranging from the repre-
sentation of signs to recall was felt. Also, as the subjects at-
tempt to remember the signs, the role of language in memory
during the rehearsal condition of the subjects was revealed. The
goal of this research is to create a strategy to determine the
early lack of inner speech application in old age, that is, recog-
nition of unnatural rehearsal can be a warning for memory de-
mentia. Lack of sonic motion is probably the major reason why
inner speech has not been sufficiently dealt with. Playing a
memory-refreshing role, inner speech is a significant value to
memory, which is subject to gradual process of senescence,
especially a growing tendency among the elderly to use exter-
nal mnemonic devices such as resorting to others for reminders
or using notes to help remind things, which is indicative of
inner mnemonic weakness. Therefore, showing the lack of ef-
fective utilization of self-directed speech as an inner mnemonic
can more closely explain the role of this language in deficiency
of old age memory and can help the therapy of patients with
dementia. It also can prevent occurrence of dementia by keep-
ing inner speech and private speech active. Because learning
things opens direction in memory and review of them stabilizes
this direction and when we use to combine schemata, organiza-
tion, and elaboration, these directions join together, and thus,
the memory ability will develop.
Multi-component Working Memory
Baddeley and colleagues (Baddeley, 1992; Baddeley &
Hitch, 1974; Baddeley and Logie, 1999) developed a multi-
component working memory in which we can see two major
storage systems including visuo-spatial sketchpad and the pho-
nological loop. One central executive system coordinates two
storage systems. The phonological loop holds speech-based
information that is the acoustic and phonological properties of
words, letters, and numbers together. The phonological loop
has been fractionated into a passive phonological store and the
active articulatory subvocal rehearsal process, inner speech.
(Logie, 2003, p41) that refreshes traces of memory. The visuo-
spatial sketchpad deals with visual information. This system
has been fractionated into a passive visual cache and an active
spatial inner scribe (Logie, 1995). The episodic buffer is able to
combine different information from phonological loop and
visuo-spatial working memory into a single representation
(Baddeley, 2000, 417-423).
Because reading ability of monosyllabic words is remained
in many of the patients with dementia, overt maintenance re-
hearsal test can be done in these cases. In advanced cases of
illness, the patient is not able to distinguish some of the letters
of the word being read. However, this matter is not seen in all
the patients: some patients gradually lose their reading ability
N. JAHANGIRI ET AL. 625
and letter distinction. In showing the importance of self-di-
rected speech and its role on verbal memory, we should follow
up the way in which we can measure language in the mainte-
nance of mental health. Therefore, we designed and performed
maintenance rehearsal test to compare the rehearsal pattern of
healthy subjects and patients: from this comparison, we found
out the differences of rehearsal in them. Ability, rapid repetition,
and congestion rehearsal are assessed in this way. In old age,
decreased reading ability is possible, and sentence writing may
be impossible or hard with tremor or hand deficiency. Cases of
hearing weakness that causes individuals to become unsuc-
cessful in their interview response to the Mini-Mental State
Examination have been regarded in subject selection.
A total of 18 participants were examined; 9 persons were
healthy, and 9 persons were affected by amnesia. Participants
ranged in age from 60 - 85 years (mean age 72.27 yrs), s.d =
8.29 and composed of 14 men and 4 women. The MMSE score
for the controls with apparently normal cognition was higher
than 25, and that for patients with amnesia was 0 - 18.
Maintenance R e h e a r s a l Test.
This study is based on overt rehearsal that follows up the
congestion rehearsal patterns. We used monosyllabic words
with frequency values between 10 and 50 per million and fa-
miliarity values of 100. These words were selected from MCR
Psycholinguistics Data Base related to other reports (Wilson
1988), and in the translation of ideal words to Persian with
consideration of semantic limits, word lists were one composed
of 24 practice cards and 16 original cards with insertion of
word on every card, which was fixed for all the subjects and
examined separately. Practice lists for the subjects were in the
form of 2 test lists composed of 12 cards. First, the practice
cards were presented for all the participants, and they vocalized
words on the cards. During this time, thery were guided on how
they would proceed. Then, the participants were given the op-
portunity to prevent the interference between the rehearsal of
the original list and the practice list because some words in the
practice list might have remained in the long-term memory
(LTM). The time was variable for the controls and the patients
with amnesia. Then, the original list was presented for 1 sec,
and the participants had a mean gap of 6 sec for vocalizing the
new words and overt rehearsal of all the words from the first.
The participants were guided continually. This was the manner
of giving possible active rehearsal to the participants.
Results and Discussion
Comparison of the Whole Word Repetitions in Two
Groups (Figure 1)
The Mann-whitney U test was used to analyze the difference
in the number of whole word repetition in all 16 positions be-
tween the two groups. The results show that the number of
whole word repetition in the controls (first group) is signifi-
cantly more than that of the patients (second group). Box dia-
gram consists of five sections: minimum of data, maximum of
data, mean, first quarter, and third quarter. Minimum of data
shows the group down level, maximum of data shows the group
upper level, first quarter includes 25%, and third quarter in-
cludes 75% of data in every group. This box diagram shows
that 25% of the controls had whole word repetitions of ap-
proximately 78, and 50% of them had 80 repetitions. Also, the
repetitions of the 75% of them was more than the mean. In the
first qroups, the outlying data show that the individual whole
word repetitions had a difference with the mean of the whole
group word repetitions. The mean of whole repetitions for the
controls was 83.22, and that for the patients was 36.56. Because
the P-value of this test is α = 0.05, then the difference between
the two groups is significant. Therefore, in the following, we
consider these three-word repetitions in the two groups.
Comparison of the Whole Word Repetition in all the
16 Positions in the Two Groups (Figure 2)
To compare the whole number of every word repetition in all
the 16 positions, the Mann-whitney U test was used. The results
show that primacy effect exists only in controls. This effect is
the movement of primary words toward the end of the list
through rehearsal. The primacy effect continues until the sev-
enth word in the rehearsal of the controls, but this effect is sig-
nificant until the third word. In general, the first, second, and
third words have been repeated in the controls more than the
group with dementia.
The control group, with a mean of 24.22, has repeated the
first word in all of its 16 positions more than the patient group
with a mean of 3.89. Because α = 0.000 < 0.05, then the differ-
ence of the first word repetition between the two groups is sig-
The control group, with a mean of 17.44, has repeated the
second word in all of its 16 positions more than the patient
group with a mean of 2.78. Because α = 0.001 < 0.05, then the
difference of second word repetition between two groups is
The control group, with a mean of 5.78, has repeated the third
GroupN Mean Std.
1 9 83.22 24.035 8.012
2 9 36.56 26.097 8.699
omparison of the whole word repetition in the two grou ps. C
N. JAHANGIRI ET AL.
The mean of every word repetition in all the 16 positions.
1―First word (P-value = 0.000) (Figure 3) 2―Second word (P-value = 0.001) (Figure 4)
Group N Mean
1 9 24.22 9.922 3.307
2 9 3.89 4.512 1.504
GroupN Mean Std.
1 9 17.44 7.699 2.566
2 9 2.78 2.333 .778
Comparison of the first word repetitions in the two groups: (1-control
Comparison of second word repetitions in the two gr o ups.
N. JAHANGIRI ET AL. 627
3―Third word (P-value = 0.014) (Figure 5)
Group N Mean Std.
1 9 5.78 5.069 1.690
2 9 1.44 1.740 .580
Comparison of third wo r d r ep e t i t i o n s in the two groups.
word in all its 16 positions more than the patient group with a
mean of 1.44. Because α = 0.014 < 0.05, then difference of
third word repetition between the two groups is significant.
The Mean of Word Repetitions in Each Position for
the Two Groups (Figure 6)
The Mann-Whitney U test was used to compare the word
repetition number in every position. The results indicate that
there is no significant difference between the two groups in the
three positions: first, eleventh, and sixteenth: however, in other
positions, the controls had more whole number of word repeti-
tion significantly in every position than the second group.
The Mean of Retrieved Words per 15 Positions
The results show that in all of 15 positions (except the first
position), the controls recalled the more word number than the
According to Brown et al, any general retrieval deficit could
lead to impaired rehearsal and to a selective impairment of
primacy (Brown et al, 2007, p257).
The Percentage of Word Repetitions Belonging to
Previous Words (Figure 8)
To compare the percentage of previous word repetition ability,
the Mann-Whitney U test was used. The results show that the
controls have repeated previous words significantly more than
the second group (P-value = 0.000).
Word repetitions in each posi t i o n f o r two groups.
N. JAHANGIRI ET AL.
The percentage of repetitions belonging to previous words.
Group N Mean
1 9 .6122 .15398 .05133
Previous Words 2 9 .0711 .09707 .03236
The percentage of word repeti tions belonging to previ ous words.
Approximately 61% of words repeated by the controls be
long to those of previous positions, and only 7% of words were
repeated by the patients.
It case shows within-list retrieval of two groups. There is an
individual whole previous word repetition of 43% in minimum
and an individual whole previous word repetition of 80% in
maximum in the control group. Also, there are outlying data
among the controls with whole previous word repetition of
Analysis of Maintenance Rehearsal Test Result in the
Working Memory Model (Figure 9)
The shape of the phonological short-term memory process of
Baddeley et al. (1984) cited in Jacquemot and Scott (2006, p
481) shows two separated entrances of visual and auditory in-
puts to the working memory (Baddeley, 1992; Baddeley &
Hitch, 1974; Baddeley and Logie, 1999). According to this
model, the auditorily presented material enters the phonological
store automatically, and the visually presented material must be
articulated before it can enter the phonological store (Hanley,
1997, p 429).
In this study the patients have had 7% within-list retrieval
and the controls 61% within-list retrieval. Then the controls
have done necessary repetition for transferring of visual inputs
to their working memory phonological loop but the patients
have not done. We have presented to participants the lingual
N. JAHANGIRI ET AL. 629
Jacquemot & Scott, 2006, p 481.
visual inputs therefore, the inputs can not access to phonologi-
cal store unless the participants can read and repeat them. 7%
within-list retrieval of patient group in overt rehearsal test sug-
gests that their vocal rehearsal process is weak. Also, it implys
that their articulatory subvocal rehearsal process is inactive too.
Use of the overt rehearsal procedure does not change the basic
effects observed in free recall (Tan & Ward, 2000, cited in
Brown et al, 2007, p257).
Therefore, when there is deficiency of articulatory rehearsal,
the possibility of memory traces vita will lose a few seconds
after the relevant word representation. Verbal language, that is,
auditory input, and writing language, that is, visual input, in-
teract with the working memory phonological loop. This stor-
age system includes two articulatory rehearsals and mainte-
nance of speech-based information. When an individual sees
and vocalizes pertinent word, and if the rehearsal part in the
memory phonological loop is active, this word will remain in
the maintenance part of this store. Repeating the word after
seeing and vocalizing, whether mentally or overt, is the reason
that word remains in the working memory phonological loop.
Every repetition itself is a lingual input; this auditory input
enters the working memory phonological loop and the inner
speech by means of continuous repetition, termed “maintenance
rehearsal,” protects that input in the memory. Then, the inner
speech role is to create a rehearsal state for maintaining the
memory phonological loop inputs. In this respect, rehearsal can
maintain only phonological representation, whereas refreshing
can maintain any representations through focus of attention.
Both of them aid in the maintenance of verbal information
(Camos et al., 2010). Participants were encouraged to apply the
cumulative rehearsal and there was no phonological similarity
within our list. Therefore all of the participants just operated
like the instruction. However, overt rehearsal should have the
necessary speed. Low speed of speech provides less rehearsal in
a limited time. Therefore, it provides fewer subsequent inputs
in patients than in healthy people. If we carry out this rehearsal
with a period of approximately 6 sec for gaps between the rep-
resentations in experimental conditions, we can find within-list
retrievals from the repetition ability and its subsequent, creating
latter inputs for the working memory phonological loop, which
they indicate as active rehearsal in the verbal memory. We
consider a human memory span limitation of 7 ± 2. Despite the
representation of 16 words which can be affected by the pref-
erence of the participants. The other researchers tested articula-
tory suppression effect on phonological loop in healthy people.
They tried to suppress rehearsal. Salame and Baddeley (1982)
claimed that articulatory suppression reduced overall levels of
serial recall because the items were unable to gain access to the
phonological store (Hanley, 1997, p424). Suppression during
visual input impedes rehearsal by occupying the rehearsal loop
(Toppino & Pisega, 2005, p375).
They suppressed rehearsal in healty people, but our findings
suggest that rehearsal decreses in dementia per se. The results
are the same, reduction of recall. On the other hand, the pri-
macy effect reflects the use of rehearsal to carry forward
early-list item selectively (Tan & Ward, 2000, cited in Brown et
al, 2007, p259). And the controls had such primacy effect until
the seventh word, but the patients had not. Through a compari-
son of the rehearsal manner of the two groups, impaired pri-
macy effect in group with dementia, it is concluded that the
pattern of overt rehearsal of the healthy group is different from
the pattern of patients suffering from dementia (Figures 2 and
6). Brown et al. (2007) reported classic amnesic pattern of sub-
stantially impaired primacy about one anterograde amnesiac
Subvocal rehearsal is the state of inner speech utilization,
which exists in normal older people, and we present it in ex-
perimental conditions. The passive rehearsal pattern is seen in
older people with dementia, who are not able to repeat stimulus
effectively and use inner speech. Thus, the rehearsal patterns of
the controls and the patients are different.
There are no primacy effects in the group with dementia, and
there are various repetition loses. In other words, the percentage
of the number of repetition belonging to previous words de-
clines, and the mean number of retrieved words per 15 posi-
tions included in the within-list retrievals significantly de-
creases. There is inner speech in the form of subvocal repetition
in normal old age individuals, and it is responsible for convert-
ing and maintenance of visual input to verbal silent input by
rehearsal. Therefore, the inner speech in the form of subvocal
repetition is a storage system, and also, it is possible that pri-
vate speech can be charged for the transition of visual input to
retrieval part of the phonological loop. Then, we deal with
whisper or more audible speech which can keep visual inputs in
memory phonological loop in the verbal repetition condition.
Then, private speech in the form of vocal repetition is a storage
system. Thus, deficiencies of inner speech and private speech
storage system will lesson the possibility of retrievals from the
phonological loop in older people affected by dementia.
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