His Inner PeaceAlzheimer’s disease (AD) has long been considered a detrimental form of dementia. With over 35 million individuals globally living with dementia and this number predicted to triple in the next thirty years (World Health Organization, 2012); it is now vital that effective pharmacological treatments help modify the disease and improve individual’s quality of life — as current pharmacological treatments have only been effective in relation to relieving the severity of symptoms.

As a result researchers have looked to investigate whether other non-pharmacological treatments can supplement pharmacological treatments to aid AD sufferers in their battle with the disease.

There is growing amounts of evidence demonstrating that music interventions are effective in treating dementia such as relieving symptoms and eliciting positive physiological effects — whether it be listening, music therapy or musical activities.

Impaired memory is the most common symptom of AD individuals and most research has focused on the effect visual and verbal stimuli has on AD.

However researchers such as Cuddy have investigated the possibility of memory for music which may be accessed differently than visual and verbal stimuli.

For example there are cases of musicians with AD continuing to play their instrument and learning new pieces of music despite their impaired memory due to their disease (Cowles et al, 2003).

This is backed up by evidence that suggests lyrics in a song aid verbal memory, increase the speed of learning and elicit recall of a greater number of words than spoken words in people with mild AD (Simmons-Stern et al, 2012).

Could it be that there is a difference in learning and recall of verbal information in a song between AD sufferers who have music experience and those who don’t?

According to a new study by Baird and colleagues at Macquarie University in Sydney, music training may facilitate memory function in AD patients.

Musicians and non-musicians (AD and healthy) were compared on tasks that assessed the impact of sung vs spoken words on learning and recall of verbal information.

To be classed as a musician (healthy or AD), 50+ years of musical experience (vocal or instrumental) and playing of instrument once a week was required. This was self-reported or in the case of AD participants, verified by a family member.

Each participant listened to a voice read (spoken word) or sung six pieces of information that consisted of a day, time and task and were asked to try and remember the information spoken or sung. For example “On Monday at 9 o’clock he took aspirin… On Friday at 5.30 she posted a letter.”

As the information was spoken the researchers prompted recall by asking “what did he/she do?” and to recall as much information as they could.

If the participant didn’t recall all six pieces of information they were prompted with more questions about the other pieces of information they had missed — this was to inform the participant about what they should look out for in the next learning trial.

The sung version was the same amount of time as the spoken word version and was performed a cappella (without musical accompaniment) to the melody of a familiar song to Australians.

To reduce the chance of individuals performing better or worse on the sung or spoken presentations due to factors such as tiredness; the presentation of the modalities (sung and spoken information) was counterbalanced.

Every participant heard the items sung and spoken until they recalled all the information correctly (max of five learning trials).

Once the individual had completed this verbal recall task they were asked to complete standard cognitive tests for 30 minutes such as the Mini-Mental State Examination (MMSE).

As the verbal recall had been tested once it was now time for the delayed recall assessment which took place 30 minutes after the cognitive tests.

Once completed, recall of the spoken/sung items was assessed via prompts related to the actions, days and times mentioned in the items. This was done once more 24 hours later by phone call after reminding participants of the tasks they had done the day before.

After this 24 hour recall task, six yes/no questions were presented to the participant, e.g. “Did he task an aspirin?” Three questions were deliberately incorrect.

As expected the MMSE score showed the AD group to have greater cognitive impairment than healthy participants regardless of music experience.

The healthy group also performed better on all aspects and assessments that took place and recalled all information sung or spoken prior to a fifth learning trial. Whereas only 40% of AD individuals succeeded in doing so.

Interestingly musicians with AD showed better total learning of sung information at immediate and delayed recall than non-musicians with AD, suggesting effects of their music training assisted the processing of melodic information compared to non-musicians who are likely to have found learning sung information more difficult than spoken word. This could be due to the need to process melodic information which is more demanding and they haven’t been trained to do so.

It may be that non-musicians had to infer lyrics of a song and code sung information as spoken word which may explain the lack of difference between musicians and non-musicians in spoken word recall.

Despite the negative effects of AD on memory, processing of melodic information may be a preserved cognitive skill for musicians.

When considering the recall after delays (30 minutes, 24 hours later, yes/no questions) it is important to note that there was no difference in performance on sung or spoken word tasks between healthy and AD individuals regardless of music training

When comparing healthy and AD musicians, healthy musicians showed higher performance in total learning of sung and spoken information and sung information 24 hours later.

However there was evidence of enhanced memory performance of two AD musicians (out of five AD musicians) who were able to recall information after a delay. Both with over 65 years musical experience which is similar to that of the healthy group and demonstrates the positive effect of music training on memory in the elderly population.

Baird did note that there are some limitations with the study carried out.

The healthy group performed far better than the AD group in this study as expected. This could mean that the tasks used measure different cognitive functions in the two groups.

However if the task was to be made more challenging to accommodate the healthy group then the AD group may suffer and be at risk of a floor effect.

The study carried out is based on a small sample size which is further reduced when categorizing participants into musicians with AD for example. This may reduce the generalizability and reliability of the results.

However for this research to be carried out it was always going to be conducted on a small subgroup of participants due to the rare nature of musicians with AD and research in this area only referring to case studies – meaning this study is the first to provide empirical evidence to the scientific community in this area.

With these limitations and other methodological concerns in mind, Baird and colleagues suggested future research should record the information that participants needed prompting for, as the information may show important distinctions between healthy and AD individuals.

Also with the learning trials taking place face-face with the researchers and the delayed recall over the phone; a lack of situational and contextual cues could have influenced the results. Therefore future research should investigate whether learning and retrieval contexts impact the recall of information in people with AD.

There were small differences shown in favour of musicians with AD performing better on the MMSE than non-musicians. It may be that music training enhances cognitive functioning in other areas besides consolidation of melodic information – however this finding should be considered with caution due to the small difference.

Even though the findings from this study didn’t show any difference between sung or spoken information on recall in healthy or AD groups; it is interesting to see that music training improved memory performance in those with AD.

The reasons for this are unclear but it may be specific aspects of music training help improve memory and therefore there is a need for future research to investigate what these aspects could be.

 

References

Baird,A., Severine, S., Miller, L., & Chalmers, K. (2016). Does music training facilitate the mnemonic effect of song? An exploration of musicians and nonmusicians with and without Alzheimer’s dementia, Journal of Clinical and Experimental Neuropsychology.

Cowles, A., Beatty, W. W., Nixon, S. J., Lutz, L. J., Paulk, J., Paulk, K., & Ross, E. D. (2003). Musical skill in dementia: A violinist presumed to have Alzheimer’s disease learns to place a new song. Neurocase, 9, 493–503.

Cuddy, L., Duffin, J., Gill, S., Sikka, C., Brown, R., & Vanstone, A. (2012). Memory for melodies and lyrics in Alzheimer’s disease. Music Perception, 29, 479–491.

Simmons-Stern, N. R., Deason, R. G., Brandler, B. J., Frustace, B. S., O’Connor, M. K., … Budson, A. E. (2012). Music-based memory enhancement in Alzheimer’s disease: Promise and limitations. Neuropsychologia, 50, 3295–3303.

World Health Organization. (2012). Dementia: A public health priority. Geneva: World Health Organization.