Maarten Frens
My main research aims to
unravel the neurophysiological basis of motor learning. The specific aim is to
elucidate the link between the cellular mechanisms of neural plasticity in the
cerebellum (e.g. LTD), and learning at a systems level (i.e. electrophysiology
and behaviour). I do behavioural and electrophysiological experiments in rabbit
and genetic mouse models. Furthermore I do behaviour and fMRI studies in healthy
humans, as well as patients (see below). In am currently in the process of
establishing a new lab for cerebellar work in primates (in collaboration with
Prof de Zeeuw and Prof Roelfsema).
Over the last 5 years my
lab has established several new techniques that enable experimentation on a
level that is not possible elsewhere. These include:
- We have custom-designed an apparatus for Gaussian white noise stimulation of the
vestibular and visuomotor system, which allows for a thorough signal
theoretical analysis of the oculomotor reflexes. VOR learning
(changing ones oculomotor response to vestibular stimulation based on visual
input) has proved to be an excellent model for such an approach.
- We have developed sequences for optimal functional magnetic imaging (fMRI)
of the cerebellum. Due to anatomical constraints this regions of the brain is
typically hard to image. Partially therefore, most
fMRI studies have focused on the neo-cortex, often neglecting the cerebellum.
This, combined with a state-of-the-art MRI-compatible eye tracker allows us to
make high quality images of human motor learning, e.g saccade adaptation.
- We are the only lab that can record eye movements of mice in three dimensions.
This is an important step, since genetic mice have proven to be a fruitful model
for studying the link between motor behaviour and the underlying synaptic
plasticity. Our recording method allows to study the motor behaviour in
its full dimensionality.
- Together with the Vanderbilt University, we have developed a new technique to
stimulate neurons in the CNS using laser light, allowing for stimulation
sites that are a factor smaller than the classical electric stimulation.
Patient studies are
directed at patients that have a deficit that can help elucidate the mechanisms
of motor control. Typically these are patients with either genetic or
paraneoplastic disorders, or patients with chronic pain .
Based on the latter research we have developed a model that describes the two-way interaction
between motor behaviour and chronic pain (CANS, or RSI). We are in the process
of starting a spin-off company (KINEOS research), that will further develop this
model, and that will market it as prevention software.
Within our department, my research
group works in close collaboration with the group of dr. Jos van der Geest