Measuring Temperature and Phantom Taste Related Brain Activity in - - PowerPoint PPT Presentation

• M. Skinner*1,2, S. Eldeghaidy2, R. Ford1, T. Giesbrecht3, A. Thomas3, S. Francis2, J. Hort1.

Measuring Temperature and Phantom Taste Related Brain Activity in Thermal Tasters Compared to Thermal non Tasters

1 Sensory Science Centre, University of Nottingham, UK. 2Sir Peter Mansfield Imaging Centre, University of Nottingham, UK. 3Unilever R&D, Port Sunlight, UK.

What is thermal taster status?

Thermal taste phenotypes

• Thermal taster (TT)
• Thermal non taster (TnT)
• Salty
• Umami
• Metallic
• Minty
• Spicy

WARMING stimuli COOLING stimuli

Bitter Sour

TTs are more sensitive to other oral stimuli

• Taste
• Trigeminal

(Hort et al, 2016; Green & George, 2004)

Sweet

Food Choice?

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(Cruz & Green, 2000) (Yang et al, 2014)

Exploring thermal taste phenotypes

Multidisciplinary approach

• Sensory Science & functional Magnetic Resonance Imaging (fMRI)

Perceptual response

• Captured by sensory evaluation techniques

Brain activation

• Captured by fMRI techniques

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• Brain activation maps show areas of the

brain involved in the response to a stimulus

Study aims

Perceptual response

• Can we identify the temperature range at which phantom

taste is perceived during temperature stimulation?

• Does this differ across TTs?

Brain response

• Do we see activation in the gustatory cortex when phantom

taste is reported?

• Is there a difference in temperature related brain activation in

the somatosensory cortex across thermal taste phenotypes?

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Identify mechanisms involved in the phantom taste response?

Thermal taste phenotyping

• Classify TT/TnT
• Measure perceived temperature intensity

Warming trial Cooling trial

2 replicates Recruited

• 12 TT/12 TnT

5 General labelled magnitude scale (gLMS)

5°C trial

Modified phantom taste testing

10 replicates Temporal taste response

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40°C trial Rating Rating

Reproducibility of phantom taste

• Phantom taste is reproducibly reported across replicates
• Phantom taste is perceived at a specific temperature range

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Inter-individual responses

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TTs perceive phantom taste at different temperature ranges

Inter-individual responses

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fMRI brain imaging

• 3 T Philips Achieva scanner, 32-element SENSE head coil
• fMRI data acquired with double-echo gradient EPI (TE: 20 ms, 45 ms),

3mm3 isotropic voxel size, 36 transverse slices, TR = 2.5 s

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fMRI testing

Control task

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Subject 07 Subject 07

40°C trial 5°C trial

Phantom taste related brain activation in TTs

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Brain activation in regions associated with taste processing in TTs

Taste cortex (anterior insula)

Are gustatory nerve fibres activated by temperature in TTs?

Is ‘phantom’ taste really a phantom?

fMRI data analysed by Dr Sally Eldghaidy-Sir Peter Mansfield Imaging Centre UoN

Temperature response across thermal taste phenotypes

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TTs have greater temperature related brain activation than TnTs

fMRI data analysed by Dr Sally Eldghaidy-Sir Peter Mansfield Imaging Centre UoN

Oral somatosensory areas

Conclusions

• TTs perceive phantom taste at variable temperature

ranges during the temperature trials

• Brain regions associated with taste processing are activated

in response to temperature stimulation in TTs, accounting for the perceived ‘phantom’ taste

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• TTs have greater temperature related brain activation

than TnTs These findings aid in elucidating the mechanism/s driving phantom taste perception and the heightened oral sensitivity to temperature in TTs

SSC

• Joanne Hort
• Rebecca Ford
• Martha Skinner

Acknowledgments

Thank you for your attention!

SPMIC

• Susan Francis
• Sally Eldeghaidy

Unilever

• Anna Thomas
• Timo Giesbrecht
• Marco Hoeksma

www.nottingham.ac.uk/biosciences/research/research-themes/taste-map/taste-map.aspx

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