Preprint alert: Interested in the intra and interhemispheric anatomical hierarchical organization of the neocortex? See our new study @SWC_Neuro together with @TeichertManuel @UKJ_Jena & Troy Margrie, online now + 🧵:

In @eLife: Layer 6 corticocortical neurons are a major route for intra- and interhemispheric feedback

3/3 Thanks to a fun collaboration between the @SWC_Neuro , @swc_niu and the Animal Navigation group at the University of Oldenburg (my hometown).

2/3 The atlas is accessible via the standardized BrainGlobe Atlas API: This allows the community to directly align their own experimental multimodal data to the common coordinate space of the atlas, see example:

1/3 This atlas was created by whole-brain imaging of multiple blackcap brains using serial-section two-photon tomography, followed by average template construction and expert anatomical and functional segmentation.

Please see our manuscript on a digital 3D bird brain atlas of a migratory and magnetoreceptive species (Eurasian blackcap) online now 🐦‍⬛🧭🧠: See also short thread👇.

How do individual neurons distinguish internal from external motion ? Please see this amazing study by my colleagues at Troy Margrie lab @SWC_Neuro

Our study on how to overcome off-target optical stimulation-evoked cortical activity in the mouse brain in vivo is now peer-reviewed published, please see:

5/5 Please also see this study which shows that this off-target activation can impact behaviour:

4/5 So please consider factors such as the duration, intensity and wavelength, the fiber implantation site and the proximity of both the stimulation and recording site to the eyes and visual pathway in your experiment.

3/5 The potential mechanism: Unintended off-target activation of endogenous opsins due to laser light striking the back of the retina which causes activity in downstream cortical circuits. By light-adaptation of the retina this can be overcome.

2/5 The solution: We show that as little as 20 lux ambient light is sufficient to prevent red, orange and blue light-evoked cortical activity. Only at very high laser intensities does red wavelengths continue to cause significant cortical firing.

1/5 The issue: Shining red, orange or blue wavelengths of light into the mouse brain in the dark in the absence of exogenous opsins at intensities commonly used for in vivo experiments results in pronounced non-specific activation of cortical cells.

Are you working with in vivo optogenetics? Ever wondered what the impact of shining laser light within the brain in the absence of exogenous opsins has on neuronal activity? PLEASE SEE & READ 🧵👇.work done @SWC_Neuro, thx Mateo Velez-Fort & Troy Margrie.

RT @HiranmayJoag: Going to #FENS2024? .Please drop by my poster PS01-26AM-300: "Are newly formed dendritic spines necessary for long-term m….

RT @SWC_Neuro: Will you be at #FENS2024? Don’t miss the latest work from our researchers! @FENSorg

Are you at #FENS2024? .Please drop by my poster PS06-28PM-506: ."Cortical layer 6 mediates intra- and inter-hemispheric connectivity and its hierarchal organisation".Friday 28 June 14:00 – 17:30 (Poster Session 06) .wt @TeichertManuel & Troy Margrie

5/5 The observed interhemispheric disparities are explained by a pronounced relative increase in Layer 6 corticocortical cells in sensory and motor (v-a-sm) but not in prefrontal, medial or lateral contralateral cortical areas (pf-m-l).

4/5 We observe that the cortical hierarchy of the input patterns reveal hemispheric differences with the contrahemisphere input patterns indicating strong feedback modulation.

3/5 Layer 6 corticocortical cells play a dominant role in intrahemispheric feedback. This is even more pronounced for interhemispheric communication.

2/5 Areal input from the two hemispheres displays bilateral symmetry in relative input weights.