The midbrain is an important subcortical area involved in distinct
functions such as multimodal integration, movement initiation,
bottom-up, and top-down attention. Our group is particularly interested
in cellular computation of multisensory integration. We focus on the
visual part of the avian midbrain, the optic tectum (TeO, counterpart to
mammalian superior colliculus). This area has a layered structure with
the great advantage of distinct input and output regions. In chicken,
the TeO is organized in 15 layers where visual input targets the
superficial layers while auditory input terminates in deeper layers. One
specific cell type, the Shepherd's crook neuron (SCN), extends dendrites
in both input regions. The characteristic feature of these neurons is
the axon origin at the apical dendrite. The molecular identity of this
characteristic region and thus, the site of action potential generation
are of particular importance to understand signal flow and cellular
computation in this neuron. We present immunohistochemical data of
structural proteins (NF200, Ankyrin G, and Myelin) and ion channels
(Pan-Na-v, Na(v)1.6, and K(v)3.1b). NF200 is strongly expressed in the
axon. Ankyrin G is mainly expressed at the axon initial segment (AIS).
Myelination starts after the AIS as well as the distribution of Na-v
channels on the axon. The subtype Na(v)1.6 has a high density in this
region. K(v)3.1b is restricted to the soma, the primary neurite and the
axon branch. The distribution of functional molecules in SCNs provides
insight into the information flow and the integration of sensory
modalities in the TeO of the avian midbrain.
«
The midbrain is an important subcortical area involved in distinct
functions such as multimodal integration, movement initiation,
bottom-up, and top-down attention. Our group is particularly interested
in cellular computation of multisensory integration. We focus on the
visual part of the avian midbrain, the optic tectum (TeO, counterpart to
mammalian superior colliculus). This area has a layered structure with
the great advantage of distinct input and output regions. In chicken,
the TeO is orga...
»