Study of Neural Correlates of Mandarin Tonal Production

with Neural Network Model

Department of Electrical Engineering, National Central University, Jhongli 320, Taiwan, ROC

Chairman:Hung-Chi YangPresenter: Yue-Fong GuoAdvisor: Dr. Yeou-Jiunn ChenDate: 2012.12.26

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Chao-Min Wu* Tao-Wei Wang

Received 6 May 2011; Accepted 15 July 2011; doi: 10.5405/jmbe.934

OutlineIntroduction

Overview of the DIVA model

Method

Results

Discussion

Conclusion

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Introduction Population ages

Communicative disorders

Improve the diagnosis and treatment of speech problems

Analyzing Mandarin speech production

Neural correlates of Mandarin tonal production

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Introduction Physiological model

To Examine speech articulation

A neural-network-based direction into DIVA models （ Directions Into Velocities Articulator ）Simulate neural correlates of speech productionTo determine the neural correlates of Mandarin tonal

production

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Introduction The DIVA model

Originally designFixed preset pitchTonal production was not considered

The modified DIVA modelProduce four types of Mandarin tonesSimulate brain activity regions

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Overview of the DIVA model Adaptive neural network model

The stepsA word or a syllable inputGenerate articulatory movement commandsShape of the vocal tract required to produceSpeech synthesizer produce speech sound

Produces a sequence of numberRepresent the brain activity regions and levels

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Overview of the DIVA model

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Method DIVA model

Mandarin tonal production is described and incorporated

Simulating brain activity are presented

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MethodMandarin tonal production

Chao proposed a five-point-scale

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MethodPitch scaling function

Approximated with the fourth-order polynomials Multiplied by the pitch periods of the first tone

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Method

To modify the motor commandsCorresponding articulator to generate

The tonal speechThe corresponding brain activity regions

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MethodSimulation of brain activity

Baseline conditionSpeaking conditionCorresponding brain areas

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MethodIn the first simulation

Given vowel with different tones(/a/, /a/, /a/, and /a/)Were analyzedVerify whether capable of tone production

In the second simulationThe brain activity regions of two different vowels with a

given tone(/a/-/u/) The difference of the corresponding vowel brain activity

regionsDetermine whether the original function maintained

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MethodIn the third simulation

Give vowel with different tonesA comparison among brain activity regions

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ResultsIn the first experiment

According to the first two formant frequenciesThe produced f0 contoursCapable of Mandarin tonal production

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ResultsIn the second experiment

motor cortex, pre-motor cortex, auditory cortex, SMA, and cerebellum

(a) the vowel /a/ and (b) the vowel /u/

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ResultsDifference between the production of different vowelsDifference in the activation in the lip and laryngeal areas

and the SSM area

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ResultsIn the third experiment

Difference in the larynx area and the somatosensory cortex

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DiscussionPrevious study find the tone-relate activity regions

Prefrontal cortexPitch judgment tasks

Left middle temporalWord-level comprehension

Right inferior frontal gyriPrecentral gyri

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DiscussionThe DIVA model simulating brain activity

Motor cortexAuditorySomatosensoryCerebellum

The differences between simulation and study

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ConclusionBecause these regions are not included in the DIVA

model.

Future studyFocus on the tone-related brain regionNeeded to include these region in the DIVA modelTo investigate the role

The frontal and temporal lobes

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The end

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