study of neural correlates of mandarin tonal production with neural network model

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 agesCommunicative disordersImprove the diagnosis and treatment of speech

problemsAnalyzing Mandarin speech productionNeural correlates of Mandarin tonal production

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Introduction Physiological model

To Examine speech articulationA 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 modelThe steps

A 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 11

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 study

Focus 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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