Background
Autism Spectrum Disorder (ASD) is a
developmental disorder that affects a wide range of behavioral and
communicative abilities in humans; this includes difficulty in
communicating and interacting with others, restricted interests, and
repetitive behaviors that affect the daily lives of autistic
individuals. Individuals who are affected by ASD can display varying
symptoms ranging in severity. Some common social inability signs of
ASD include inconsistent eye contact, unusual tone of voice,
inability to adjust to social or verbal cues, and ignoring others
(National Institute of Mental Health, 2024). While the cause of ASD
remains unknown due to the complex nature of this disorder, this has
prompted scientists to explore different therapy approaches to this
disorder to try to improve the quality of life for individuals on
the ASD spectrum. One form of treatment has been music therapy.
Music therapy involves the use of music as a therapeutic
intervention to address the behavioral and social symptoms of ASD
individuals (Applewhite et al., 2022). Music may be a more
accessible way of interacting since a musical message does not have
to be conveyed verbally, and therapy could be enacted in any
comfortable environment for the ASD individual (Pater et al., 2022).
However, current music therapy practices only use classical music as
a treatment option for autistic individuals. The lack of diverse
genres used in therapy may limit the outcomes of music therapy (Fu
et al., 2023). Music has the potential to influence moods, feelings,
and thoughts. Different aspects of music genres are also often
associated with different emotions. For example, pop music contains
the same repetitive melody and is generally played in a major key,
which is associated with positivity and happiness (Ahmad & Rana,
2015). However, there are many different factors in a song or piece,
and it is difficult to pinpoint the exact factor of how music can
affect emotions and behaviors. So, this study uses classical music
and pop instrumentals to reduce some variability in music. This
project aims to study the behavioral responses Drosophila exhibits
when listening to different frequencies of music. The use of
different frequency ranges within the same study allows for a
clearer understanding of how each genre of music affects autistic
individuals. Using behavioral assays such as the locomotion
behavioral assay shown to the left (Figure 1), the study records the
locomotion responses of Drosophila after listening to the different
genres of music. The research could lead to potentially personalized
music therapy instead of following the common classical music bias
and demonstrate how specific genres of music uniquely impact
ASD-induced Drosophila’s behavioral responses. In turn, the results
could potentially be generalized to the human population for further
research and study. Drosophila was used in this study as it is a
model organism that shares genetic similarities to humans. Around 75
percent of human disease is homologous in Drosophila, with
homologous genes functioning in synaptogenesis, synaptic plasticity,
protein synthesis and degradation, transcription, and lipid
homeostasis; Drosophila also has many similar neural pathways as
humans (Ueoka et al., 2019, Greenspan, R., 2012). Two types of
Drosophila were used, wild-type and ASD-induced Drosophila. The
latter lacks the dfmr1 protein. The dmfr1 gene is the homolog gene
to the human fmr1 gene and is essential for RNA-binding and
translational regulation. Mutations or deletions of the dfmr1 gene
in Drosophila result in phenotypes that mimic symptoms of ASD, such
as altered social interaction, attention deficits, hyperactivity,
and repetitive actions due to the disruption of neural circuit
development and synaptic plasticity. Specifically, it causes Fragile
X Syndrome (FXS), the most common form of hereditary mental
retardation, and the genetic condition commonly cited as the leading
heritable cause of autism and mental retardation. Although estimates
vary, one in every 2500 to 7000 males and one in 2500 to 11000
females experience FXS (Bartholomay et al., 2019, Wan et al., 2000).
Ultimately, utilizing Drosophila as a model organism, this study is
manageable and replicable, which could lay the groundwork for future
Drosophila research projects.
