How connectivity rules affect cortical behaviour

Analytical examination of eigenvalue spectra

24th April, 2015
An example eigenvalue spectrum for a sparse network.

How does the behaviour and stability of a neuronal network depend on the connectivity rules used to build it? A common approach is to build many stochastic instances of a network, tweak the parameters, simulate and analyse, and then try to derive an impression about stability. We instead used an analytical approach, to directly relate connectivity rules and parameters to bounds on stability.

Information in thalamic input to visual cortex

Comparing and quantifying the information passed from two thalamic pathways into V1

1st February, 2016
Mismatch and summation between running speed and visual flow speed; distributions of information passed to V1 from thalamus.

The pulvinar is a complex of higher-order visual nuclei in the thalamus. It is heavily interconnected with many cortical and subcortical areas, and has been shown to exert strong influence on visual cortical activity. The pulvinar may be important for attentional gating of visual information and integration of visual and behavioral information, but knowledge about its function is still very limited. In particular, it is unknown what type of information this thalamic hub conveys to different cortical areas.

Putting vision into context

And adding context to vision

21st December, 2015
This optical illusion shows how strongly the context of a visual scene influences what we see, and how that context can sometimes mislead us. The three people in the picture are exactly the same size. However, because our brain judges the size of an object based on its perceived distance, the person at the back seems to be further away and therefore appears larger.

Our brain does not faithfully interpret visual information, but instead uses a complex mixture of prior experience and context to shape our perception of the world. We described a pathway in the brain for this contextual information, from the mouse thalamus to visual cortex.