Abstracts - Association for Chemoreception Sciences

MSG on NaCl is evidently highlighted in the limbic lobe. On the
contrary the positive effect of NaCl on MSG elicited activations
in areas more common to taste perception. The conjunction
analysis revealed common activated areas for the two tastants in
the primary (SI) and secondary (SII) somatosensory cortex,
premotor cortex, but also in secondary taste areas. With regard to
lateralization within the gustatory system, the BOLD contrast for
the MSG stimulus was significantly bigger on the right side of the
brain when the stimulus was presented to the left side as
compared to the right side presentation of the stimulus. Moreover
the opposite contrast for MSG highlighted only few brain areas
including the left orbitofrontal cortex. The contrary appeared
when the stimulus was NaCl. This result suggests a
contralaterality of the brain response to the MSG stimuli but an
ipsilaterality for the NaCl stimuli whit a strong and general right
sided lateralization of the brain for saltiness.
#P297 POSTER SESSION VI:
PERIPHERAL AND CENTRAL TASTE;
PERIPHERAL OLFACTION
Electrical neuroimaging of gustatory perception in humans
Kathrin Ohla, Julie Hudry, Johannes le Coutre
Nestlé Research Center Lausanne, Switzerland
Questions of how in general, and where and when in particular,
gustatory percepts are represented in the human brain remain
largely unanswered despite decades of research. Electrical
neuroimaging of gustatory perception has been hampered by
difficulties with stimulus control because recording of eventrelated
brain electrical responses (electroencephalography, EEG)
requires temporally precise stimulus presentation to obtain good
summation of the signal across trials. This is difficult to achieve
with flowing stimuli in solution. Aim of this study was to
investigate cortical response patterns of gustatory perception over
time. For this, a gustometer, which met the requirements for the
recording of event-related responses, was employed to present
bitter, salty, sour, sweet and umami solutions to human volunteers
while EEG was recorded. Taste qualities were identified equally
well by panelists. Intensity and pleasantness judgements, however,
varied between participants. Brain responses were analyzed with
respect to their time courses, spatial distributions and neuronal
generators. We present series of stable maps (microstates) for each
tastant and we show overlaps between tastants and point out
differential activation patterns. Moreover, we show that these
response patterns varied between participants thus bearing
important implication for the grand-averaging technique
commonly used in EEG research. Finally, we report the neuronal
generators of each stable map, which comprised areas previously
associated with the processing of taste and food-related stimuli. In
particular the insular cortex and the orbitofrontal cortex are
involved. The findings are discussed in the framework of current
knowledge on gustatory perception in the human brain.
#P298 POSTER SESSION VI:
PERIPHERAL AND CENTRAL TASTE;
PERIPHERAL OLFACTION
Multiple Neuronal Subpopulations emerge from the Olfactory
Placode During Development
Alexandra M. Miller 1, 3, 4 , Lydia R. Maurer 1 , Charles A. Greer 1,2,3
1
Department of Neurosurgery, Yale University School of Medicine
New Haven, CT, USA, 2 Department of Neurobiology,
Yale University School of Medicine New Haven, CT, USA,
3
Interdepartmental Neuroscience Program (INP) New Haven,
CT, USA, 4 Medical Scientist Training Program New Haven,
CT, USA
During olfactory development a migratory mass (MM) (Valverde
et al., 1992) forms in the mesenchyme as cells and axons exit the
olfactory placode (OP) and begin to approach the nascent
olfactory bulb (OB). Subpopulations of cells, collectively termed
MM cells, emerge including ensheathing cells, odor-receptor (OR)
expressing cells, and OMP+ cells from the main olfactory
epithelium (OE), and GnRH+ cells from the vomeronasal (VNO)
organ (Valverde et al. 1992; Conzelmann & Breer 2002;
Schwanzel-Fukuda 1999; Miller et al. unpublished data). As the
axons extend across the basal lamina, beginning at embryonic day
(E) 10, they join and interdigitate among the MM cells. Elsewhere
in the nervous system pioneer neurons may serve as guideposts
for later extending axons (i.e. Zimmer et al., 2010); the cells of the
MM may function similarly in olfactory nerve development. We
tested the hypothesis that molecular diversity, or spatial-temporal
patterning of the MM cells, contribute to the ongoing coalescence
of subpopulations of OSN axons as they extend toward the
developing OB. We show that by E12 the MM cells are
heterogeneous, containing subpopulations distinct from those
described (such as the GnRH+ and OMP+ cells) and migrating
from both the main OE and the VNO. Expression patterns are
complex, but occur in combinatorial phenotypes that can include
expression of: MAP2, OMP, DNER, GnRH, DCX, Lectins,
NQO1, and CXCR4. The diversity among the MM cells may be
related to the heterogeneity of the OSN axons, each of which
expresses only 1 of ~1,200 ORs and converge with like-axons.
It is plausible to hypothesize that the subpopulations of OSN
axons rely on specific subsets of MM cells to provide the
intermediate cues that influence axon organization and trajectory
as they approach the developing OB. Acknowledgements:
Generously supported by NIH/NIDCD/NIA
#P299 POSTER SESSION VI:
PERIPHERAL AND CENTRAL TASTE;
PERIPHERAL OLFACTION
Development of a Mouse Embryonic Stem Cell Model for
Neurogenesis and Localization of RARa and RARg in
these Cells
FaMitah Q. Buchanan 1 , Elvin A. Woodruff III 2 ,
Cecile Rochette-Egly 3 , Mary Ann Asson-Batres 1
1
Tennessee State University Nashville, TN, USA, 2 Vanderbilt
University Nashville, TN, USA, 3 Institut de Génétique et de
Biologie Moleculaire et Cellulaire Strasbourg, France
P O S T E R S
Our laboratory has shown that vitamin A-deficient (VAD)
postnatal rats have significantly reduced numbers of mature
olfactory neurons (ORNs). VA is a precursor for retinoic acid
(RA), a growth factor that positively influences embryonic
development and cell differentiation. It is hypothesized that
Abstracts are printed as submitted by the author(s)
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