Melodic intonation therapy as an effective facilitator of language function recovery: A DTI study in people with non-fluent aphasia
-
1
National Tsing Hua University, Center for Cognition and Mind Sciences, Taiwan
-
2
Hsinchu Cathay General Hospital, Department of Rehabilitation, Taiwan
-
3
National Taiwan University Hospital Hsin-chu Branch,, Department of Rehabilitation, Taiwan
Generalisation of treatment effects on various levels of language functions is the goal of speech and language therapy. Previous studies on melodic intonation therapy (MIT) (e.g. Keith & Aronson, 1975; Norton et al., 2009, Schlaug et al., 2009) have provided evidence on improvement of word production as well as connected speech. Yet, little attention is paid to establishing the relationship between treatment gains and neuroplasticity in language-related tracts. Understanding the underlying mechanism provides further insight into how the damaged networks are compensated. Therefore, the study set out to 1) investigate the effect of melodic intonation therapy on language-related tracts and 2) provide a model accounting for the potential neural reorganization in people with aphasia.
The study employed diffusion tensor imaging (DTI), a magnetic resonance imaging technique, to investigate the treatment effect of MIT in people with non-fluent aphasia. The change of the diffusion index, fractional anisotropy (FA), of pre- and post-treatment DTI data in people who received MIT was analyzed. The investigation focused on language-related tracts (for a review, see Smits et al., 2014), such as the arcuate fasiculus (AF), superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF), inferior fronto-occipital fasciculus (FOF), and uncinated fasciculus (UF), which are illustrated in the figure.
Six people with non-fluent aphasia resulted from single left-hemisphere CVA were recruited and assigned to the MIT group or non-MIT group. Three people without aphasia were recruited as controls. The people who were assigned to MIT group received two treatment sessions per week over 4 months. Sentence production performance was recorded pre- and post- training to assess the treatment effect.
The results confirmed that, comparing to the control participants, people with non-fluent aphasia demonstrated decreased FA, which is associated to negative change of white WM connectivity. Compared to the non-MIT group, all participants in the MIT group showed not only improved sentence production but also increased FA in the WM tracts. Further, positive correlations between the language performance and FA values were found in the two language-related dorsal stream in the right hemisphere, right-AF and right-SLF. As the primary language pathway, AF connects Wernicke’s and Broca’s area, whilst SLF is linked to sound to motor mapping. Although the tracts (IFOF, ILF, and UF) located in the ventral stream did not significantly correlate with the language performance, positive response towards MIT was observed.
Overall, the study demonstrated right-hemisphere compensation. An interactive model of the dorsal and ventral streams for speech recovery following the MIT was proposed. The dorsal stream is related to motor-speech planning and the ventral stream is involved in sound-form-meaning integration. The two streams interact with each other for speech recovery. In order to construct appropriate response for articulation, the processes subserved by the ventral stream works with the speech motor movements processed by the dorsal stream. Future research may include a larger group of participants as well as various aphasia types.
References
Keith, R. L. & Aronson, A. E. (1975). Singing as therapy for apraxia of speech and aphasia: Report of a case. Brain and Language, 2, 483-488.
Norton., A., Zipse, L., Marchina, S., & Schlaug, G. (2009). Melodic intonation therapy: Shared insights on how it is done and why it might help. Ann. N. Y. Acad. Sci., 1969, 431-436.
Schlaug, G., Marchina, S., & Norton., A. (2009). Evidence for plasticity in white-matter tracts of patients with chronic Broca's aphasia undergoing intense intonation-based speech therapy. Ann. N. Y. Acad. Sci., 1969, 385-394.
Smits, M., Jiskoot, L. C., & Papma, M. (2014). White matter tracts of speech and language. Seminars in Ultrasound, CT and MRI, 35(5), 504-516.
Keywords:
aphsia,
Melodic Intonation Therapy,
DTI,
white matter microstructure,
tractography
Conference:
54th Annual Academy of Aphasia Meeting, Llandudno, United Kingdom, 16 Oct - 18 Oct, 2016.
Presentation Type:
Poster Sessions
Topic:
Academy of Aphasia
Citation:
Wang
NY,
Yang
FG,
Chiang
T and
Lai
Y
(2016). Melodic intonation therapy as an effective facilitator of language function recovery: A DTI study in people with non-fluent aphasia.
Front. Psychol.
Conference Abstract:
54th Annual Academy of Aphasia Meeting.
doi: 10.3389/conf.fpsyg.2016.68.00122
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
30 Apr 2016;
Published Online:
15 Aug 2016.
*
Correspondence:
Prof. Fan-Pei G Yang, National Tsing Hua University, Center for Cognition and Mind Sciences, Hsinchu, 30013, Taiwan, fpyang@hss.nthu.edu.tw