Department of Physics (DF)

Neurophysics group

The Neurophysics Group has the objective to study physical mechanisms underlying signal perception and transduction in the nervous system and to apply experimental physics methods to problems in neuroscience. The following research activities are related to Brain Network Dynamics.

Studying network dynamics via fast spatio-temporal imaging

We develop and extend an optical imaging platform for small animal models e.g. regarding spatial and temporal resolution and imaging depth. Different new modalities will be implemented in the future like three-photon excitation and voltage-sensitive markers.

Paoli, M., Andrione, M. & Haase, A. Imaging Techniques in Insects. in Lateralized Brain Functions: Methods in Human and Non-Human Species (eds. Rogers, L. J. & Vallortigara, G.) 471–519 (Springer New York, 2017). doi:10.1007/978-1-4939-6725-4_15
Haase, A. et al. In-vivo two-photon imaging of the honey bee antennal lobe. Biomed. Opt. Express 2, 131–8 (2010).

Oscillatory dynamics in primary odor processing

We use our advanced temporal resolution to study oscillatory features correlated to odour stimuli. We found that there are changes in the oscillatory spectrum that are odour-dependent and uncorrelated to the static amplitude code. We continue testing the interplay of spatial and temporal features in the odour code.

Paoli, M., Weisz, N., Antolini, R. & Haase, A. Spatially resolved time-frequency analysis of odour coding in the insect antennal lobe. Eur. J. Neurosci. 44, 2387–2395 (2016).

Response Latency code

We investigate the fastest possible neural code, neuronal response latencies. We find in insect primary odour processing that response latency ranks form a universal code of odour quality across individuals. It has the same prediction accuracy as the spatial code of firing amplitudes in network nodes. It contains complementary information to the static amplitude code and correlates best to the psychometric data of behavioural odour distinction.

Paoli, M., Albi, A., Zanon, M., Zanini, D., Antolini, R. & Haase A. Neuronal response latency rank encodes first odor identity information across subjects. J. Neurosci. accepted (2018).

Optogenetic network studies

We are extending the optical readout of brain function towards optogenetic brain manipulation.

The light-induced activation of single network nodesLocal optical activation of single network nodes with subsequent imaging of the whole network will allow following the progression of this activation within the brain network. This will provide a direct measure of functional connectivity and network dynamics.

Generating 3D holographic light patterns for optical activation will allow mimicking activation maps induced by natural stimuli. This will then allow to selectively test various parameters for there role in information coding.