Musical Attention Training Program and Alternating Attention in Brain ...

Musical Attention Training Program and Alternating

Attention in Brain Injury: An Initial Report ROGER KNOX HIROKO YOKOTA-ADACHI JOHN KERSHNER JEFFREY JUTAI

Bloorview University University University

MacMillan Children's Centre, Toronto, Canada of Toronto, Canada of Toronto, Canada of Western Ontario, Canada

ABSTRACT: The literature has indicated that attention deficits are common problems in brain injured clients. Dichotic listening studies have shown that alternating attention measured with a dichotic lis­ tening method is correlated with performance in learning. Using a dichotic listening paradigm, the present preliminary inquiry investi­ gated: (1) the alternating attention ability of a brain injured adoles­ cent; and (2) the effects of alternating attention sessions of a newly­ developed music therapy intervention, the Musical Attention Training Program (MATP), on the alternating attention ability in the client. The results indicated that the client's alternating attention patterns were within a normal range; yet, after the musical treatment alternating attention on the dichotic listening test performance was enhanced. Further research is required to explore the potential of the alternating attention sessions of the MATP to influence atypical patterns of at­ tention in brain injured individuals.

Claeys, Miller, Dalloul-Rampersad, & Kollar, 1989), cognitive, and communication impairments (Claeys et al., 1989; O'Callaghan, 1999) which may be caused by brain injuries. Claeys et al. (1989), for example, illustrated the effectiveness of music therapy in addressing a wide range of functional lev­ els in cognitive activity of clients with traumatic brain injury through its variety of modalities, from producing particular responses by administering musical stimuli to facilitating cre­ ative output. In a literature review of music therapy in neu­ rorehabilitation, Purdie (1997) described a general role of mu­ sic therapy in cognitive improvement "as a means of provid­ ing environmental enrichment by stimulating interactive par­ ticipation and nonverbal communication and thereby facilitating cognitive and behavioral change" (p. 210). How­ ever, there has been a dearth of empirical research examining the effects or efficacy of music therapy on attention remedi­ ation for clients with brain injuries (see Knox & Jutai, 1996 for further review and discussion), or of musical rehabilitation programs specifically designed for attention remediation for those clients. For the specific purpose of musical attention remediation, Wit, Knox, Jutai, and Loveszy (1994) developed the Musical Attention Training Program (MATP; revised version Jutai et al., 1997). This program was an adaptation of Sohlberg and Ma­ teer's Attention Process Training, which was an attention re­ mediation program for persons with acquired brain injuries (Sohlberg & Mateer, 1987). Attention Process Training (APT) addresses in order five lev­ els of attention (Sohlberg and Mateer, 1987, p. 119):

Problems with attention are frequently observed in clients with brain injuries (e.g., Wood, 1989; Sandson, 1988; Posner & Rafal, 1986). According to Wood (1987, pp. 121-122), damage as a result of brain injury causes at least four com­ ponents of attention to be affected negatively as follows: de­ crease in alertness, failure of selective attention, forced re­ sponsiveness to irrelevant stimuli, and reduced attention span. Those attention problems may prevent clients from obtaining maximal benefits of therapy (Knox & Jutai, 1996) because lis­ tening and following instructions, which are usually involved in therapeutic sessions, require information processing capa­ bility, including attention span, attention capacity and mem­ ory (Wood, 1989). Thus, rehabilitation of attention problems is often a priority for these clients (Knox & Jutai, 1996). Research has indicated that music therapy is useful for re­ mediating physical (Hurt, Rice, Mclntosh, & Thaut, 1998;

• Focused Attention: The ability to respond discretely to specific visual, auditory, or tactile stimuli. • Sustained Attention: The ability to maintain a consistent be­ havioral response during continuous or repetitive activity. • Selective Attention: The ability to maintain a cognitive set which requires activation and inhibition of responses de­ pendent upon discrimination of stimuli. • Alternating Attention: the capacity of mental flexibility which allows for moving between tasks having different cognitive requirements. • Divided Attention: The ability to simultaneously respond to multiple tasks.

Roger Knox, Ph.D., is Research Associate (Music) at Bloorview MacMillan Children's Centre, Toronto. Hiroko Yokota-Adachi, Ph.D., currently works at the Personnel Psychology Centre, Public Service Commission of Canada. John R. Kershner, Ph.D., was affiliated with the Ontario Institute for Studies in Education, University of Canada. Jeffrey W. Jutai, Ph.D., is an associate pro­ fessor in the School of Occupational Therapy, University of Western Ontario and the Director of the Psychosocial Evaluation team of the Ontario Reha­ bilitation Technology Consortium. This project was completed as part of the requirements for the second author's doctoral program at the Ontario Institute for Students in Education at the University of Toronto. The study was conducted in association with a research project funded by the Easter Seal Research Institute of Ontario and the Police Association of Ontario, and also supported in part with financial assistance from the Ontario Ministry of Health through the Ontario Rehabilitation Tech­ nology Consortium. The authors wish to thank Vivienne Wit, B.M.T., music therapist, for administrating the treatment with George. © 2003, by the American Music Therapy Association

The training consists of traditional paper-and-pencil cogni­ tive tasks, involving selectively responding to target stimuli interspersed randomly among other stimuli. Tasks include can­ cellation of target letters, numbers, words or shapes. There are

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also tasks presented on cassette tape, include responding to target letters, numbers, or words among non-target stimuli by pressing a buzzer. Similarly to Sohlberg and Mateer's APT, Jutai et al.'s MATP was designed to improve clients' attention abilities according to the five-level model. However, unlike APT, all the activities were constructed using musical components, which are as­ sumed to be intrinsically motivating. In the MATP there is no specific training of focused atten­ tion. Sustained Attention Training requires clients to detect a pre-determined percussion sound or sounds, and to press the computer spacebar upon hearing the target percussion sound or sounds. The target sounds are interspersed randomly among sets of 5 different Rock percussion or 10 different Latin per­ cussion sounds. The task addresses sustained attention in that the client must maintain a consistent response throughout this repetitive activity. Selective Attention Training requires clients to selectively at­ tend to the melodic line in an instrumental composition, and to identify a pre-determined target motive whenever it occurs in the melodic line. Upon identifying the target motive, clients are to press a key on an electronic keyboard. In Alternating Attention Training, which was the focus of this study, clients are instructed to follow a melodic line. As soon as they hear a pre-determined melodic motive, they press a key on the keyboard. When the rhythm track begins, they shift attention from the melodic line to the rhythm track and press another key to supply a drum sound as downbeat to each measure. When the rhythm track ends, they shift attention back to the melodic task component. (A more detailed de­ scription is provided in the Method section.) In Divided Attention Training, the same music and the same target motives or percussion sounds are used as in Alternating Attention Training. Instead of shifting attention from the mel­ ody line to the rhythm track, however, clients are required to attend both task components (i.e., melody and rhythm track) simultaneously. The client's task is to press a key when they hear a pre-determined melodic motive, and to press another key to supply a drum sound as downbeat to each measure. In the present study, we investigated to what extent the Al­ ternating Attention Training of the MATP would affect alter­ nating attention ability in particular for the following reasons. As discussed below, neuropsychological studies indicated that alternating attention ability measured with a dichotic listening test can be a predictor of learning (Kershner & Graham, 1995; Kershner & Micallef, 1991; Kershner & Morton, 1990). Sec­ ond, although Jutai et al.'s MATP contained a program for re­ mediating alternating attention ability, the effects of this spe­ cific program on clients' alternating attention ability remained unexamined. Thus, the purpose of this study was to examine the effects of the Alternating Attention Training of the MATP in particular, as an adjunct to a larger scale clinical study (Jutai et al., 1997). Because this study was adjunctive it was not independently designed. As an outcome measure to examine alternating attention ability, the authors implemented a dich­ otic listening testing paradigm.

Music Therapy Perspectives (2003), Vol. 21

. . . the purpose of this study was to examine the effects of the Alternating Attention Training of the MATP in particular, as an adjunct to a larger scale clinical study

Dichotic Listening and Learning Difficulties

In dichotic listening, a separate auditory stimulus is pre­ sented to each ear simultaneously. Auditory-verbal informa­ tion perceived at the right ear is easier to code and process than the same information arriving at the left ear (Kershner & Graham, 1995). This phenomenon is called a right ear advan­ tage (REA) and interpreted as an indication of linguistic spe­ cialization of the left cerebral hemisphere (Kershner & Gra­ ham, 1995). This inference is made based upon studies indi­ cating: (1) in most right-handed people the left hemisphere is specialized for linguistic processing, (2) the contralateral path­ ways (e.g., right ear—left hemisphere) are proponent over ip­ silateral auditory path way (e.g., left ear—left hemisphere), and (3) the left hemisphere is preprogrammed when activated differentially by attending selectively to the information arriv­ ing at the right ear (Kershner & Graham, 1995). In a directed attention dichotic paradigm (DAD), which is an alternating attention version of the test, individuals work on the task either in the following two procedures. In the right ear first order (REF), they are asked to report what they have heard from the right ear (RE) for a number of trials, and then to switch their attention from the RE to the left ear (LE) and report what they have heard from the left ear for the same number of trials. In the left ear first order (LEF), individuals work on the same task in the reversed order, that is, attending to the LE first and then the RE. The literature indicates that performance in reading, writing and spelling are significantly correlated with greater facility in alternating attention from the RE to the LE, as well as from the LE to the RE (Kershner & Graham, 1995; Kershner & Micallef, 1991; Kershner & Mor­ ton, 1990). That is, individuals without learning difficulties can more easily switch their attention from the RE to the LE (a weaker right ear advantage [REA] in the REF order) than those with learning difficulties. Individuals with no learning prob­ lems can more easily switch attention from the LE to the RE (a stronger REA in the LEF order) than those with learning problems. If so, brain injured clients' performance on the DAD task may suggest whether or not they may have learning dif­ ficulties that are linked to alternating attention. Thus, in the present preliminary study, the DAD paradigm was employed to examine alternating attention ability in a brain injured cli­ ent. The authors also investigated whether the alternating at­ tention sessions of the MATP procedure would change dich­ otic performance in the direction of increasing normalization (i.e., a stronger REA in the LEF order and a weaker REA in the REF order).

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Method

in our second author's extensive empirical research experi­ ence in this area. George participated in Sohlberg and Mateer Attention Pro­ cess Training (APT) program concurrent to the MATP. The oc­ cupational therapist reported that in APT training he per­ formed well on auditory sustained and selective attention tasks but was more easily distracted and had more frequent errors with alternating attention. He also participated in other music therapy sessions devoted to psychosocial issues and fo­ cused on song writing.

Subject "George" (pseudonym) was a healthy and sensitive eigh­ teen-year-old male with a closed head injury. In the accident, George hit a telephone pole while riding his motorcycle home from his part-time job in a store, and was in a coma for 14 days. He was wearing a helmet that was cracked by the im­ pact. He suffered a closed head injury and an odontoid frac­ ture, for which he was required to wear a halo brace during rehabilitation. Retrograde amnesia extended two hours pre­ injury, and post-traumatic amnesia for 30 days. Neuropsycho­ logical assessment identified an impairment in left frontal and parietal functions, and slowing of information processing con­ sistent with diffuse axonal injury. Bilateral hearing tests post­ injury were normal. When George started the rehabilitation program eight weeks post-injury, he was diagnosed by a neuropsychologist as having a closed head injury with attention deficit, based on his performance on the Paced Auditory Serial Attention Test (PASAT; revised version Neuropsychology Laboratory, Univer­ sity of Texas, Galveston, 1987), and attention remediation was indicated.1 A standard clinical assessment tool, the PASAT measures both sustained and divided attention, while placing demands on working memory (Stierwalt & Murray, 2002). In this test, clients are asked to listen to string of digits, and are required to add each number to the one immediately pro­ ceeding it. The sensitivity of the PASAT to general attention deficits resulting from traumatic brain injury has been amply demonstrated (Gronwall & Wrightson, 1981; Levin et al., 1987). George volunteered to participate in the present inquiry, which was approved by the Ethical Review Board at the Bloor­ view MacMillan Children's Centre. He began the MATP pro­ gram 14 weeks post-injury. He had no previous history of neu­ rological disorder. Before his injury he played the guitar, pre­ ferring pop and rock music, and also wrote poetry and songs. His school performance was normally on or above average. He was active in sports, particularly basketball. George reported that he used his right hand for 6 out of the 10 activities listed in the Edinburgh Handedness Inventory (Oldfield, 1971), including writing, drawing, striking a match, and using scissors, a toothbrush and a spoon. He used his left hand in throwing, and either hand in using a knife, broom, and in opening a box lid. However, it should be noted that hand-preference in writing (the right hand in George's case) seems to be the key indicator for hemispheric lateralization 1

Although the client showed an attention deficit on the PASAT when he started the rehabilitation program, by the time he began the Alternating Attention Training of the MATP his PASAT attention scores had nearly reached ceiling. However, as discussed in the text, successful performance on the PASAT re­ quires sustained and divided attention abilities and not alternative attention ability, which is the focus of this study. In fact, in cognitive rehabilitation the client performed well in sustained and selective attention tasks, but continued to show problems with alternating attention tasks according to the program occupational therapist.

Alternating Attention Training of the MATP As briefly described in the previous section, the Alternating Attention Training of the MATP involved shifting between two requirements: one was to recognize a pre-determined melodic motive and the other was to track the meter in a drum pattern. There were a total of eight trials with target motives of pro­ gressively increasing length. Although the requirements were the same across the trials, the musical form of the trials varied among them: March, Rock, Andean, Country, Asian Pentaton­ ic, New Age, Reggae, Baroque. The variety of styles was in­ tended to give the graded musical examples broad appeal for the different adolescents who participated in the MATP. All the trials were delivered on a Macintosh llvi computer in the form of MIDI files using the Music Shop software sequencer. The musical input was delivered through a 100-watt Roland keyboard amplifier with a monophonic speaker. Thus, sound was delivered externally, rather than internally (e.g., using headphones), for two reasons. First, George needed to listen to the instructions from the music therapist and to interact with her before and after engaging in the Alternating Attention Training of the MATP. Second, the therapist had to listen to the music in order to record clients' responses to pre-deter­ mined targets. An Alternating Attention Training session of the MATP in­ cluded several trials. At the beginning of each trial, music was presented with the drum track turned off. George was instruct­ ed to focus on the melodic line, and when he heard the pre­ determined melodic motive (e.g., a four-note pattern played with saxophone tone), to strike a key on beat that followed the motive that ended. At a certain point, however, the drum track was turned on. As soon as he heard the drum sound, he was to focus on the drum track (and thus ignore the melodic line), and strike a key on a Roland U-20 keyboard in order to produce a percussion sound along with the drum track at the downbeat of every measure. He was instructed to do so as long as the drum track was being presented. At certain points, however, the drum track disappeared again. He was then to switch attention back from the drum track to the melodic line, and hit a key after he heard the pre-determined melodic mo­ tive as he did before. Thus, George was to alternate attention between the melodic line and the drum track, depending upon whether the drum track was on or not. George worked on each trial twice, at slow and at fast speeds. Upon achieving 80% of correct response or better on a trial, he moved on to the next; when scoring less than 80%

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there was further pre-trial training and then repetition of the trial.

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Research Design The study employed a single subject research design with a repeated measurement. George participated in the MATP 3 times a week for 10 weeks. For the first six weeks he partici­ pated in Sustained and Selective Attention Training of the MATP, and for the final four weeks in Alternating Attention Training of the MATP. In the last three successive weeks of those four weeks, testing with the dichotic listening paradigm with CVs was conducted immediately before and after one alternating attention training session per week.

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Dichotic Listening Test with CVs and Procedures The Auditec St. Louis dichotic listening test, consisting of 30 pairs of Consonant-Vowels (CVs), was employed.2 The 30 pairs were combinations of "Pa," "Ba," "Da," "Ga," "Ta," and "Ka." Thus, for example, George might listen to "Pa" from his right ear (RE) and "Ta" from his left ear (LE). The CVs were presented with an interstimulus interval of 6 sec at the level "+3" on a Pioneer dual cassette deck through SONY ear­ phones. George wrote on a piece of paper what he heard from the directed ear (i.e., either the RE or LE) and was encouraged to guess if unsure. First, as a pretest, he received 30 trials with attention forced to the RE first and then 30 trials with attention forced to the left ear (i.e., the Right Ear First order, REF). He took a break for approximately 5 minutes, and then attended with the LE for the next 30 trials and with the RE for the following 30 trials (i.e., the Left Ear First order, LEF). He then received a session of alternation attention training of the MATP approximately for half an hour. After the treatment, the same test with the same procedures was administered (post­ test). Earphones were reversed during a two minute interval between ear orders to offset any channel differences in signal­ to-noise ratio. Testing was conducted on Wednesday after­ noons for three successive weeks. Performance was scored for the number of correct (C) responses from the attended ear and the number of intrusions (I) from the unattended ear. For ex­ ample, suppose that "Pa" was presented to George's RE and "Da" to his LE and he was asked to report what he had heard from the RE. If he reported "Pa", this response would be counted as the correct answer. If he reported "Da", this re­ sponse would be counted as the intrusion because this was a stimulus presented to his LE. Results

Laterality Index The raw scores were transformed into the lambda laterally index, Lambda = Log (RC X Rl/LC x LI) (Bryden & Sprott, 2

Pretest

Prior to the assessment using dichotic CVs, we first used a dichotic listening test with digits. This was the same type of test with dichotic CVs, except that 40 triple pairs of digits were used instead of CVs, and the client was instructed to indicate the numbers he had heard. However, there was a ceiling effect, that is, the client obtained the perfect correct scores and no intrusion for the both ears in both orders (REF, LEF). Thus, the test was replaced with dichotic CVs for the current study.

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Session Figure 7. Lambda laterally indexes over the three sessions in the right ear first order.

1981). This index provides a measure of lateralization that is independent of overall accuracy. The laterality index com­ pares the likelihood of recalling right ear CVs when attending right with the likelihood of recalling left ear CVs when at­ tending left. A positive lambda coefficient indicates a REA and a negative score indicates a LEA. Lambda scores, rather than correct scores, were used for the following two reasons. First, had George recovered more by the later sessions, it could have influenced raw scores. Lambda scores, however, adjusted these overall raw score per­ formance differences. Second, raw correct data indicate only how successful subjects are in selecting the stimuli from the attended ear, and do not show how unsuccessful they are in blocking the disturbance from the unattended ear, which is also an important component of attention. In lambda score computations, intrusions as well as correct responses are tak­ en into account. Thus, the scores indicate how successful sub­ jects are both in selecting information and in inhibiting dis­ turbance. Figure 1 shows that in REF order, George's REA was en­ hanced after receiving the treatment in session 1. However, in sessions 2 and 3, his REA after the treatment was depressed, whereas in LEF order, his REA was constantly enhanced after receiving the music treatment throughout all the sessions (Fig. 2). Previous research has failed to find a significant correlation between age and lateralization (Hiscock & Kinsbourne, 1995). Thus, we compared the score with those of adults who were

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it is an open question whether this treatment could be useful for normalizing laterality patterns in individuals who manifest deviant laterality patterns in alternating attention.

These results suggest that even in the absence of atypical alternating attention abilities, the client appeared to be able to enhance his attentional pro­ cessing by participating in the Alternating Attention Training of the MATP.

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Session Figure 2. Lambda laterality indexes over the three sessions in the left ear first order.

functioning normally with no apparent brain injury (Kershner, Shafrir, & Yokota-Adachi, 1994) with an age range between 23 and 55 (Mean = 33.22, SD = 8.19). The mean and SD for the LEF in this adult group were .944 and .530 respectively, and those for the REF were .098 and 1.126. George's lambda scores fell between the -1.064 SD and + 1.618 SD range of the normals for both pretest and posttest in three sessions. Discussion

George's alternation attention ability appeared to be within a normal range even before the treatment, as indicated by his lambda scores falling within between ±2SDs of normals. The noteworthy effects of the music treatment were the enhance­ ment of right ear advantage when the left ear was attended first and the depression of the right ear advantage when the right ear was attended first. That is, the treatment increased George's ability to shift attention on a task involving changes in hemispheric activation from the left to right hemisphere and from the right to left hemisphere. These are noted as atten­ tional abilities which are linked to academic achievement in normal and learning disabled populations (Kershner & Gra­ ham, 1995; Kershner & Micallef, 1991; Kershner & Morton, 1990). These results suggest that even in the absence of atypical alternating attention abilities, the client appeared to be able to enhance his attentional processing by participating in the Alternating Attention Training of the MATP. Further potential transfer effects to produce greater learning capacity are an exciting possibility, but are beyond this investigation. As well,

One explanation for the enhancement of alternating atten­ tion by the therapy in the current study is that the musical attention shifting and that of the dichotic listening test shared a common mechanism; activating the mechanism by the mu­ sical attention shifting task facilitated switching attention be­ tween two channels. The other explanation is related to arous­ al theory. The literature shows that the right hemisphere plays a significant role in mediating bilateral arousal level (Heilman & Van Den Abell, 1979) and maintaining the cerebral arousal state (Posner & Petersen, 1990, for review). A dichotic listen­ ing study reported that music listening activated the right hemisphere and consequently mediated a cerebral arousal level (Morton, Kershner, & Siegel, 1990). Thus, the Alternating Attention Training of the MATP might have stimulated the gen­ eral arousal mechanism in the right hemisphere and mediated bilateral hemispheric arousal, and consequently, facilitated other attention mechanisms, including the alternating or shift­ ing attention. It should be also noted that the treatment appeared to have a greater impact on alternating attention from the left ear to the right ear than from the right ear to the left ear. According to Kinsbourne (1987), each hemisphere inhibits the other through the corpus callosum in such a way that the left hemi­ sphere holds a rightward attention shifting whereas the right hemisphere maintains a leftward shifting. Each hemispheric bias is directed in the opposite direction and mutually inhibits the other. The forces each bias contains are, however, un­ equal; a left hemispheric activation powerfully generates a rightward bias, whereas a right hemispheric activation pro­ duces a weak bias which is only sufficient to hold the left hemispheric rightward bias in check. Thus, it is possible that although the musical treatment activated both hemispheres by heightening arousal as discussed in the previous section, be­ cause of such an attentional bias (Kinsbourne, 1987) the right­ ward shifting (i.e., alternating attention from the left ear to the right ear) was more strongly enhanced than the leftward shift­ ing (i.e., alternating attention from the right ear to the left ear). Limitations of the Study and Implications for Future Research

Problems with a longitudinal study with repeated measure­ ment in clinical settings include: the confounding of results through training in the use of assessment tools (Sohlberg &

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Mateer, 1987) and uncontrollable variables such as another treatment which a subject may be receiving outside the study. These problems, however, could only partially affect the cur­ rent findings. Even if the subject became familiar with the test and the task became easier for him (e.g., obtaining a higher accuracy in a later session), the lambda computations provide a mea­ surement of lateralization that is independent of overall ac­ curacy. It was not ethically acceptable to eliminate other cog­ nitive treatments in which George participated. One may ar­ gue that concurrent treatments could have affected the chang­ es of lambda scores between sessions. However, the lambda changes within a session, the central focus of our study, were not influenced by other treatments, because the posttest as­ sessment was administered immediately after the music treat­ ment. Similarly, it would have been preferable to have obtained baseline data (i.e., if three testing sessions were administered, consisting of pre-test, no treatment, and post-test) and then to have compared the baseline data with those obtained in our study. However, this was not possible because our study was an adjunct to the ongoing larger clinical study (Jutai et al., 1997). The larger study contained all the attention training components of sustained, selective, alternating, and divided attention in order. Thus, preceding the Alternating Attention Training, the client was participating in Selective Attention Training. Hence there was not a no-treatment period in which to obtain pure baseline data. Despite this limitation, the changes observed after the therapy imply a potential treatment effect, given that the assessment was conducted immediately after the therapy and also that lambda scores are independent of overall performance differences. A future study including baseline data would be desirable. In addition, to employ inferential statistics a larger sample would be necessary. It should be also noted that the present study was concerned particularly with alternating attention, among other attention abilities (e.g., focused, selective, sus­ tained, and/or divided attentions). Ceneralizability of the cur­ rent results is thus limited. Further investigation is necessary to examine the potential benefits of other attention training of the MATP, for each of the attentional components and/or other cognitive functions in brain-injured individuals. It would be also necessary to examine how the program would affect cli­ ents with brain injury who had deviated alternating attention patterns. REFERENCES

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