CRAIG WATT

ABSTRACT

The function of the phonological loop in vocabulary learning has been described in studies of children's first language (henceforth L1), adult's second language (henceforth L2), and vocabulary learning in people with learning difficulties as well as cognitive deficits.

The present study examines the phonological loop capacity in Japanese non-words and the learning of Italian vocabulary. The subjects were grouped by ability in their L2 (English), i.e. high ability and low ability. It is argued that those subjects with a higher level of ability in their L2 have a more efficient phonological loop.

Alan Baddeley first cited the phonological loop (1986). The phonological loop (henceforth PL) is an aspect of working memory that is responsible for the retention of verbal information over short periods of time." It comprises both a phonological store, which holds information in phonological form, and a rehearsal process, which serves to maintain decaying representations in the phonological store" (Baddeley, Gathercole and Papagno 1998:158).

The rehearsal process refreshes a fading representation of the input in the phonological store to prevent it from decay. Sub-vocal speech is used to rehearse the input and when Articulatory Suppression disrupts this, the input decays. The rehearsal process also converts written words and pictures into a phonological form; they can then be held in the phonological store.

The PL is the most comprehensively studied part of working memory. Phonological Similarity, Articulatory Suppression and Word Length provide evidence for the existence of the PL. In Phonological Similarity, items that are phonologically similar (e.g. hill, pill, till) are harder to recall than phonologically dissimilar items (e.g. dig, hand, cake) see Conrad & Hull (1964). Articulatory Suppression is when a subject is asked to repeat something that acts to suppress short-term memory for lists of words. An example would be repeating the alphabet while trying to memorize a list of numbers; this repetition prevents rehearsal of the numbers so that they decay (Murray 1967).

Word Length also affects memory performance. Longer spoken words are harder to recall because they take longer to rehearse, as in the study by Baddeley, Thomson, and Buchanan (1975).

There have been studies of adult subjects with brain damage who have a poor PL. Baddeley, Papagno, and Vallar (1988), studied an Italian woman, referred to as PV, who had a deficit in her short-term memory following a stroke. They first looked at PV's capacity for understanding spoken and written discourse. The effects were not significant, and the authors suggest that the PL may act as a back up rather than being a key feature in language comprehension.

The authors then conducted a follow up study to explore PV's PL capacity for new language learning. They used Russian vocabulary, as PV had no knowledge of Russian. PV had excellent general learning abilities and was asked to learn pairs of words in her native Italian, which she should learn normally, and Russian words matched semantically with an Italian word. Her performance on the Italian/Russian task was very poor. These results were believed to show that the PL may be used for "specialized language learning" (Baddeley 1999).

A connection between the PL and foreign language learning is further supported by Baddeley's (1993) study. An American graduate, who was a skilled cognitive psychology student, was shown to have a very short digit span and had great difficulty learning foreign language vocabulary. The student performed poorly on several PL tests when compared with other graduate students. His visual short-term memory was normal suggesting that there is a deficit in his phonological memory.

There are also several studies on the PL in children. A study by Gathercole and Baddeley (1989) tested four-year-old children who had been attending primary school for two months. They were then re-tested at ages five, six and eight years. The test on phonological memory involved the repetition of non-words. Non-words are words that do not exist in a language. At ages four, five and six the non-words contained two to four syllables. At age eight the non-words contained two to five syllables. In a later review of the study the authors concluded that "the superior immediate memory performance found with familiar rather than unfamiliar words arises from the additional availability of phonological specifications in long-term memory for familiar stimuli (Gathercole and Baddeley 1993).

A study of children with learning disabilities by Gathercole and Baddeley (1990) compared the performance of language-disordered children with normal children of the same age. Tests on non-word repetition showed that the phonological memory deficit of the language disordered children was central to their language development problems.

The PL is a device that supports language learning. In Baddeley et al. (1998) the authors "propose that the primary function of the phonological loop is the processing of novel speech input" (emphasis mine). The present study consists of two PL capacity tests, one using Japanese word and non-word pairs (henceforth J Test) and the other on Japanese word and Italian word pairs (henceforth I Test).

The J Test consisted of words with two, three or four syllables. Words with more than four syllables were excluded because of the word length effect. The Japanese words and non-words were selected regarding pitch. Each word - non-word pair had different pitches to prevent the possibility of giving the test subjects assistance in recall. This was to be avoided as the non-word PL test is based on unfamiliarity. Appendix A shows the J Test and the I Test vocabulary with pitch marked as H for a high pitch and L for a low pitch where appropriate. For example, Misaki consists of three syllables: L H H.

Some of the original Japanese non-words were removed from the list as they contained suffixes e.g. chu and ju. Suffixes may have given assistance to recall. All of the Japanese words and non-words, as well as the Italian words, were checked by a native Japanese speaker who is a graduate student at Durham University. None of the Italian words are possible words in Japanese. The Italian words were checked by a native Italian speaker who is a PhD student in Phonology at Durham University.

There will be a difference in performance between the recall of non-words and foreign words. Although both sets of words are new the Japanese words may be easier to recall because their phonological structure is more similar to normal Japanese words than the Italian words. The subject's long-term memory may contain phonological data from their Ll that assists the recall of the new Japanese non-words. Their long-term memory does not contain similar data for the Italian words, as it is a language they have not learned. Therefore the subjects should make fewer errors in the J Test than the I Test.

Taking both the J Test and I Test results, it is hypothesized that there will be a correlation between PL capacity and the subjects L2 (English) ability.

Subjects

Six Japanese native speakers were tested in the study. They were divided into two groups, low level L2 learners and high level L2 learners (henceforth L2-ers). L2 ability was determined through conversations with the subjects that lasted an hour and half. The fluency of the subjects during those conversations was used in placing them as low or high level learners (see below). The three low level L2-ers were males who had finished their high school education. The three high level L2-ers were females who had also finished high school education. They had studied English, their L2, for the same length of time (6 years of secondary education). They had native Japanese teachers of English during those 6 years. None of them had spent long periods of time (2 months or more) in a native English speaking country. They also had no knowledge of Italian.

Each subject was tested individually. The subject was presented with the word pairs from a cassette recording. The cassette recording was in two parts. The first part contained a Japanese speaker reading the Japanese word and non-word pairs with a short pause between. This is the J Test. The second part of the cassette consisted of the same Japanese speaker reading the Japanese words and an Italian speaker reading the Italian words. This is the I Test.

For each of the PL capacity tests the subject listened to a word pair (e.g. "misaki kaipan"). They then listened a second time except that this repetition did not contain the non-word (for J Test) or the Italian word (for I Test). They then had to recall the missing word (e.g. "Misaki ________"). This procedure was repeated through each word pair in the list, i.e. a first listen, then a second listen with recall. After the J Test there was a short pause while the cassette was changed for the I Test.

The subject's responses were recorded onto cassette. These responses were marked as either correct or incorrect. The judgment of a correct response was based on it matching the original recording. This meant that a mispronunciation in pitch for the Japanese non-words was marked as incorrect.

The subject's L2 ability was graded in terms of fluency. Fluency, in this paper, is defined as the ability to listen and respond to questions in the L2 (English) and this was determined by conversations. The same questions were asked to each learner so that they would all have the same input to respond to. Questions for judging fluency:

• How long have you been in Durham?
• Do you like it here?
• Tell me about your family.
• What places have you been to in the UK?

Fluency was graded by pronunciation, word choice, speed, and grammatical accuracy.  

Table 1: Errors in the Phonological Loop Capacity Test with Japanese non-words

Key: Sl to S6 = subjects numbered one to six. Number in italics = error total

Table 1 shows the low level learners made an average of six errors in the non-word PL capacity test while the high level learners made an average of three errors.

Table 2: Errors in the Phonological Loop Capacity Test with Italian words

Table 2 shows that the low level learners made an average of seven errors in the Italian PL capacity test while the high level learners made an average of five errors. Both groups found the PL Capacity Test with Italian words more difficult than the non-word test. The average number of errors on both PL Capacity tests combined was seven for the low level learners and four for the high level learners.

Table 3: Fluency, in L2, of subjects

Table 3 shows the fluency in the subjects L2, which was graded from one to ten. One indicates low fluency and ten indicates high fluency. The average fluency of the low level learners was three, while the average fluency of the higher level learners was seven.

Table 4: Calculations for value of `r' (correlation coefficient)

ey: S=Subject; X=PL Test; Y=Fluency. r = +0.55 variance overlap= 0.30 (30%)

Table 4 shows the calculations for working out the value of `r'. The correlation coefficient has a value of +0.55, which indicates a moderate correlation. The variance overlap, which shows the degree of correlation, equals .30.

The First Hypothesis, that performance in the J Test will be better than performance in the I Test, is inconclusive. Although the subjects did make fewer errors in the J Test the figures are very similar. Subject 2 (S2) made six errors in the J Test and seven errors in the I Test a difference of only one error. Furthermore the difference in the number of errors between the J Test and the I Test is only two for all other subjects. To be certain that this hypothesis is strongly supported it will clearly be necessary for a further study that tests a larger number of subjects.

The Second Hypothesis, that there will be a correlation between the PL Tests and L2 ability, is moderately supported. The variance overlap of 0.30 shows that the common variance between the PL Tests and Fluency was 30%. This figure would have to be higher to strongly support the hypothesis. Again the low number of subjects has influenced the data. A higher correlation may have been reached if more subjects had been tested and that those subjects displayed greater range of L2 ability.

Grading the subject's fluency could have been more rigorous. In addition to asking the preset questions, the subjects could have been given an English listening task. This would be a test of the subjects listening ability in their L2. Any previous L2 testing, in Japan or the UK, was not taken into consideration due to time constraints. This may have proven a more reliable indication of fluency than interviews.

The J Test and the I Test data was recorded onto cassette, although all attempts were made to make this as clear as possible some errors may have occurred because of lack of clarity on the recording rather than PL Capacity. This could be prevented by having a native Japanese and/or Italian speaker read the word pairs to the subjects.

The quote from Gathercole et al. (1993), see above, is supported by the better performance by subjects on the J Test compared with the I Test. Although both tests contained new words the J Test's non-words may be easier to recall because of Japanese phonological specifications in long-term memory. However, as the difference in errors between the J Test and I Test is not conclusive this needs further investigation.

Although the results of this paper were not conclusive it does seem to indicate that the Phonological Loop is an important factor within second language learning. The study of the American graduate by Baddeley (1993), mentioned above, gave evidence that a deficit in the PL can hinder or even prevent the acquisition of foreign language vocabulary. In the present study the low level L2 learners may have a lower level of ability in their second language because of a similar deficit. However, because the results are inconclusive it is not clear that their poor ability in their L2 is due to a deficit in the PL. Repeating the present study with a larger pool of subjects may show that low level L2 learners do tend to perform weakly in PL tests when compared with high level L2 learners. In such a case a students PL would be a factor to consider alongside others that affect ability in L2 learning such as motivation, standard of tuition, general intelligence et cetera. The phonological loop may be one factor amongst others that affect the acquisition of foreign language vocabulary.

In this paper I have described the phonological loop and cited previous research in this area. Two Phonological Loop Capacity Tests were described as well as the judgment of the subject's fluency. I proposed two hypotheses. Neither of these was conclusively supported and I have suggested further steps that could be taken to provide more robust support for them. Changes to the procedure were recommended. Finally, I described how other factors along with phonological loop capacity affect the acquisition of foreign language vocabulary.

Misaki (LHH) Ohuro (LHL) Hanabi (HLL) Agari (LHH) Katsura (HLL) Omiyage (LHHH) Chikara (LHL) Machigai (LHHL)

Momen (LHH) Shukan (LHHH) Karuta (HLL)Dojo (HLLL)

Totemono (LHHL) Tokage (LHH) Yumei (LHHH) Odenwa (LHLL)

meppa (HLL) onya (HLL) humo (HL) nakiro (LHL) jangyoo (HLLL) mumido (HLL) daiseki (LHHH) ryobi (HLL)

gochiyo (LHHH) kanhaku (LHHL) seiyoi (LHLL) umikin (LHHH) zasuho (HLLL) kumowa (LHH) moriku (LHHL) kino (LH)

Hwa Kang Journal of TEFL, Number 11, 2005, pp. . Copyright 2005. Language Center, Chinese Culture University.

http://www.hkjtefl.org/2005-Watt-Loop.html

Last updated:  31/05/05 PM

Craig Watt received his M.A. in Applied Linguistics, with a specialization in ELT, from Durham University in the UK.  He was a teacher trainer at a college in Vietnam before moving to Taiwan. He joined the teaching staff at Chinese Culture University, Taipei, in 2004.