Neuroplasticity changes of rat brain by musical stimuli during fetal period

Fetal development of the central nervous system is an important and sensitive
stage which is affected by many external and internal stimuli. This study aimed to investigate
effect of musical stimuli on fetal rat brain.
Materials and Methods: In this experimental study, twelve female Wistar rats were selected
and evenly assigned to control and musical groups. The females were mated with
a male rat of the same genotype. Musical group was exposed to classic music with 60
dB power for 90 minutes twice per day from 2nd to 20th day of gestation. The control rats
were handled similar to the musical group, but were not exposed to music. Before parturition,
all the dams were anesthetized, and their blood samples were obtained and used
for corticosterone (COS) measurement. They were transcardially perfused by electron
microscope (EM) fixative agent. The fetal brains were extracted intact and used for slice
preparation. Horizontal slices were made for electron microscope preparation, and images
were taken and analyzed in terms of cell density and morphological changes.
Results: EM observation indicated significant morphological difference in cellular and intercellular
spaces between the two groups. Music-treated fetuses had significantly higher
cell density in parietal cortex and music-treated dams had lower COS level.
Conclusion: It was concluded that prenatal music would have a great impact on neuroplasticity
of fetal rat brain, at least indirectly. Although the rat fetuses cannot hear until birth, music-induced
reduction in COS blood level of dams might be the reason for neuroplasticity of fetal brain