Hanna Heikkinen

Hanna Heikkinen

BRAHE post doctoral researcher

hanna.heikkinen [at] aalto.fi

Room IM209 at AMI-Centre, Otakaari 5I

Postal Address: AMI-centre Aalto School of Science PL 13000 00076 Aalto

Tel.: +358 50 437 1587

Vision Systems Physiology


I'm an engineer with PhD in biological physics and biomedical engineering. I have combined experimental and theoretical approaches to study how the basic building blocks of vision are constructed, in the eye and in the brain.


Research interests

Having studied the very first vital steps of vision - photoreception and its modulation - for my PhD, I am currently trying to understand signal processing in the subsequent stages of the visual system. My research concentrates on contextual modulation of visual signals and the tuning of neuronal responses in the cortex and in the retina. I am especially interested in signal processing at the primary visual cortex as well as the genesis and spatial properties of the BOLD response.

During a 3 year post doctoral research position via the BRAHE collaboration network between Aalto University and University of Helsinki, I have founded a novel research line based on modeling the neural networks of the brain. This work combines cell and network level electrophysiology to noninvasive functional imaging, and aims at a large scale biomimetic network model of the visual cortex. Currently the model has been applied for studying the relation between cell level electrophysiological data and functional neuroimaging signals. The future directions of the work aim at understanding how the networks of the developing brain organize to optimally process relevant information.


Publications

Vanni S, Heikkinen H (2015): Onko aivoissamme käyttämätöntä kapasiteettia? (in Finnish) Duodecim, in press

Heikkinen H, Sharifian F, Vigario R, Vanni S (2015): Feedback to distal dendrites links fMRI signals to neural receptive fields in a spiking network model of the visual cortex, Journal of Neurophysiology, DOI: 10.1152/jn.00169.2015

Vanni S, Sharifian F, Heikkinen H, Vigario R (2015): Modeling fMRI signals can provide insights into neural processing in the cerebral cortexx, Journal of Neurophysiology, DOI: 10.1152/jn.00332.2014

Heikkinen H, Vinberg F, Pitkänen M, Kommonen B and Koskelainen A (2012): Gain and kinetics of mouse rod photoreceptors in the isolated retina and corneal electroretinogram. Invest Ophthalmol Vis Sci, 53:5653-5664.

Heikkinen H, Vinberg F, Nymark S, and Koskelainen A (2011): Mesopic background lights enhance dark-adapted cone ERG flash responses in the intact mouse retina: a possible role for gap junctional decoupling. J Neurophysiol, 105:2309-2318.

Heikkinen H, Nymark S, Donner K, and Koskelainen A (2009): Temperature dependence of dark-adapted sensitivity and light-adaptation in photoreceptors with A1 visual pigments: a comparison of frog L-cones and rods, Vis Res, 49:1717-1728.

Heikkinen H, Nymark S, Donner K, Koskelainen A (2008): Mouse cone photoresponses obtained with electroretinogram from the isolated retina, Vis Res 48, 264-272.

Nymark S., Heikkinen H., Haldin, C., Donner, K., Koskelainen, A. (2005): Light responses and adaptation in rat retinal rods at different temperatures, J Physiol. 567:923-38.


Recent conference abstracts

Heikkinen H, Sharifian F, Vigario R, Vanni S (2014): Bridging spatial spread of fMRI and neural responses in a recurrent network model of the primary visual cortex. Bernstein Conference for Computational Neuroscience, Göttingen, Germany

Heikkinen H, Sharifian F, Vigario R, Vanni S (2013): Dendritic filtering can bridge functional magnetic resonance imaging and neural responses in a recurrent network model of the primary visual cortex. Society for Neuroscience meeting abstract, nanosymposium presentation 408.11/2013, San Diego, Ca.


Lectured courses

2008, 2010, 2012, 2014 Neurobiophysics (6-8 cr) University of Helsinki, Dept of Biological and. Environmental Sciences

2011 Living state physics 2, electrophysiology (6 cr) Aalto University, Dept. of Biomedical Engineering and Computational Science