Selective impairment of musical emotion recognition in patients with amnesic mild cognitive impairment and mild to moderate Alzheimer disease

Background

Patients with Alzheimer disease (AD) and amnesic mild cognitive impairment (aMCI) have deficits in emotion recognition. However, it has not yet been determined whether patients with AD and aMCI also experience difficulty in recognizing the emotions conveyed by music. This study was conducted to investigate whether musical emotion recognition is impaired or retained in patients with AD and aMCI.

Methods

All patients were recruited from the First Affiliated Hospital of Anhui Medical University between March 1, 2015 and January 31, 2017. Using the musical emotion recognition test, patients with AD (n = 16), patients with aMCI (n = 19), and healthy controls (HCs, n = 16) were required to choose one of four emotional labels (happy, sad, peaceful, and fearful) that matched each musical excerpt. Emotion recognition scores in three groups were compared using one-way analysis of variance (ANOVA) test. We also investigated the relationship between the emotion recognition scores and Mini-Mental State Examination (MMSE) using Pearson's correlation analysis test in patients with AD and aMCI.

Results

Compared to the HC group, both of the patient groups showed deficits in the recognition of fearful musical emotions (HC: 7.88 ± 1.36; aMCI: 5.05 ± 2.34; AD: 3.69 ± 2.02), with results of a one-way ANOVA confirming a significant main effect of group (F_(2,50) = 18.70, P < 0.001). No significant differences were present among the three groups for the happy (F_(2,50)=2.57, P = 0.09), peaceful (F_(2,50) = 0.38, P = 0.09), or sad (F_(2,50) = 2.50, P = 0.09) musical emotions. The recognition of fearful musical emotion was positively associated with general cognition, which was evaluated by MMSE in patients with AD and aMCI (r = 0.578, P < 0.001). The correlations between the MMSE scores and recognition of the remaining emotions were not significant (happy, r = 0.228, P = 0.11; peaceful, r = 0.047, P = 0.74; sad, r = 0.207, P = 0.15).

Conclusion

This study showed that both patients with AD and aMCI had decreased ability to distinguish fearful emotions, which might be correlated with diminished cognitive function.

Musical and Cognitive Abilities in Older Adults with Mild Cognitive Impairment

The objective of this cross-sectional study was to determine the extent and nature of self-reported musical abilities in persons with mild cognitive impairment (MCI). We recruited 60 older adults with a diagnosis of MCI from the Alzheimer's disease Core Center. We evaluated self-reported musical abilities using the Goldsmiths General Musical Sophistication Index. We examined correlations between musical abilities and neuropsychological measures of verbal learning and memory, processing speed, executive function, verbal fluency, naming and visuoconstructive abilities, while controlling for key demographic and participant characteristics. Older adults with MCI reported varying degrees of musical abilities. Nearly half of participants reported that they did not engage in regular, daily practice of a musical instrument. When adjusting for key demographic and participant characteristics, we found modest associations between four musical ability subfactors (active engagement, perceptual abilities, musical training and emotional engagement with music) with three cognitive abilities: verbal fluency, executive function and verbal naming. Except for the emotional engagement with music subfactor, none of the remaining musical ability subfactors correlated with any demographic or participant characteristics. While our study findings provided further support for the relationship between musical and cognitive abilities in older adults with MCI, this relationship warrants further investigation.

Music and dementia

There is an increasing incidence of dementia in our aging population, and consequently an urgent need to develop treatments and activities that may alleviate the symptoms of dementia. Accumulating evidence shows that persons with dementia enjoy music, and their ability to respond to music is potentially preserved even in the late or severe stages of dementia when verbal communication may have ceased. Media interest in this topic has contributed to the public perception that music abilities are an "island of preservation" in an otherwise cognitively impaired person with dementia. In this chapter, we review the current literature on music cognition in dementia and show that there has been very scarce rigorous scientific investigation of this issue, and that various types of music memory exist and are differentially impaired in the different types of dementia. Furthermore, we discuss the recent development of music activities as a nonpharmacological treatment for dementia and highlight the methodological limitations of the current literature on this topic. While it has been reported that music activities can improve behavior, (particularly agitation), mood, and cognition in persons with dementia, recent large-scale randomized control studies have questioned the specificity of the effect of music and found that it is no more beneficial than other pleasant activities. Nevertheless, music is unique in its powerful ability to elicit both memories and emotions. This can provide an important link to individual's past and a means of nonverbal communication with carers, which make it an ideal stimulus for persons with dementia.