![]() ![]() This sub-nucleus consists only of excitatory thalamocortical neurons, which project into cortical layer IV and form collaterals into layer Vb and layer VI as they ascend through cortex (Pierret et al., 2000). In rodents primary sensory whisker information is relayed from the whiskers through brainstem nuclei onto neurons in the ventral posterior medial part of the ventral basal nucleus of the thalamus (VPM). Beyond these general limitations of the in vitro setup, the strong local inhibitory physiology of S1 will probably also actively contribute to the spatial limitation of the response. In the absence of the continuous barrage of subthreshold excitatory postsynaptic potentials in vitro, they therefore fail to respond to single pulse stimulation of the thalamus (Laaris et al., 2000). For example, voltage-sensitive glutamatergic NMDA receptors of layer III function as coincidence detectors. This spatial confinement is in part due to the fact that in brain slice recordings in vitro, polysynaptic propagation and general background neuronal activity is attenuated because of the large number of severed neuronal projections and the absence of neuromodulators (Hájos and Mody, 2009). In vitro, stimulation of the thalamocortical afferents, even at high stimulus amplitudes, leads to voltage sensitive dye imaging (VSDI) activity confined to two layers only in the rodent primary somatosensory whisker cortex (S1, Higashi et al., 1999 Laaris et al., 2000 Itami et al., 2001 Laaris and Keller, 2002 Llinás et al., 2002 Urbano et al., 2007). The detailed characterization of the parameters of these networks may provide tools for further research into the complex dynamics of large dendritic networks and their role in cortical computation. Our findings suggest, that at least early cortical processing takes place in two separate dendritic networks that may stand at the beginning of further parallel computation. We found evidence of differences in the plasticity between the first two response peaks compared to the remaining six peaks as well as differences in short-term plasticity between the VSDI response and the LFP. Finally we investigated the short-term dynamics of both the VSDI signal and the local field potential (LFP) in response to a train of eight-pulses at various frequencies in both these layers. DiI fluorescent staining further revealed that thalamocortical axons project on to these two networks in the typical barrel like form, not only in the granular but also in the IGL. ![]() We identified the precise location and dimensions of two clearly distinguishable dendritic networks, one in the granular layer (GL) IV and one in the infragranular layer (IGL) V and VI and showed that they have different physiological properties. This preparation was used here to investigate the first stage of cortical processing in the large postsynaptic dendritic networks as revealed by voltage sensitive dye imaging (VSDI). Photomatix Pro offers both exposure fusion (also known as exposure blending) and HDR tone mapping.The in vitro thalamocortical slice preparation of mouse barrel cortex allows for stimulation of the cortex through its natural afferent thalamocortical pathway. By taking views under several exposures and processing them in Photomatix Pro, you can create a panorama that will show details in both the dark and bright areas of the scene. A panoramic scene is almost always a high contrast scene - you can’t limit your view to areas with the same brightness when shooting a 360° panorama. Photomatix Pro is designed for productivity - automatic blending, unlimited stacking, easy comparison of results and batch processing save hours of masking and layers work in image editing programs. The tone mapping tool of Photomatix can turn them into great-looking images. Shadowless hazy sunlight or an overcast sky usually results in dull-looking photographs. Just enable the Auto Exposure Bracketing feature of your camera, and let merge your photos into an image with extended dynamic range. No need to acquire expensive lighting equipment -and carry it- when you shoot high contrast scenes. Photomatix Pro merges photographs taken at varying exposure levels into a single HDR image that reveals both highlight and shadow details, with options for automatically aligning hand-held photographs, removing ghosts, and reducing noise and chromatic aberrations.
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