FEDERATION OF EUROPEAN NEUROSCIENCE SOCIETIES
9th FENS Forum of Neuroscience
5-9 July 2014 – Milan, Italy
http://fens2014.neurosciences.asso.fr/
PRESS RELEASE
EMBARGOED UNTIL TUESDAY 8 JULY 2014, 11:15 CEST / 10:15 BST
LAZY EYE TREATMENT IN ADULTS:
NEW INSIGHTS ON BRAIN PLASTICITY
Amblyopia, or 'lazy eye', a disorder causing reduction in one eye's visual capacity, affects 4% of
the world's population. The most effective treatment method so far has been the 'pirate
solution': covering the healthy eye, allowing development of the affected eye, until complete
recovery. However, best outcomes generally involve early treatment before the age of eight. At
the FENS Forum of Neuroscience in Milan, Dr Alessandro Sale, a researcher from the CNR
Neuroscience Institute in Pisa, described a new strategy that might enhance visual capacity in
adult amblyopic subjects. In animal models, the disorder was treated in a non-invasive way via
a strategy based on optimisation of environmental stimuli.
Adult nerve cells in the visual cortex are not 'plastic' enough to display sufficient recovery from
severe developmental deficits. For this reason, amblyopia recovery has proven to be very
difficult beyond the end of childhood. But recent experiments at the CNR Neuroscience Institute
found a new non-invasive strategy that could be very promising for amblyopic adults:
'environmental enrichment'.
“The first set of experiments was done a few years ago on animals bred in complex
environments rich in social, cognitive and motor stimuli,” said Alessandro Sale, the
neurophysiologist who led the research together with Lamberto Maffei, president of the Italian
Academy of Sciences (Accademia Nazionale dei Lincei). Dr Sale described this research to
delegates at the FENS conference. “In contrast to subjects reared in standard simplified
environments, adult rats bred for three weeks in enriched enclosures recovered their visual
perceptual capacities — in particular, the ability to distinguish the finest of spatial details in the
external world.”
More recently, Dr Sale’s team demonstrated that is also possible to induce a complete recovery
of visual capacities in adult amblyopic rodents through more focused environmental enrichment
strategy. For example, motor stimuli and voluntary physical activity proved to be very effective,
as well as visual stimulation tasks engaging visual perceptual learning processes.
This striking environmental enrichment recovery effect directly depends on changes occurring at
the brain level. In particular, it is due to a reduction of GABA (the central nervous system's
prime inhibitory neurotransmitter) and an increase of BDNF (a protein playing a key role in
developmental processes and neuronal plasticity). Moreover, Dr Sale’s data provide evidence of
a marked strengthening of synaptic plasticity in cortical circuits of the primary visual cortex in
enriched animals.
“Subsequent studies demonstrated that enriched environment effects can also be reproduced
through replacement of environmental stimuli with fluoxetine, a drug widely used in humans for
treatment of several psychiatric disorders,” explained Dr Sale. “For this reason, fluoxetine
seems to be included among those useful drugs able to reproduce or to enhance the
environmental effects on brain plasticity.”
According to the Pisa CNR group, the new insight of this research lies in the possibility to favour
a type of brain 'self-cure.' This is a completely novel perspective for traditional medicine, named
by the researchers 'endogenous pharmacotherapy'. “It is commonly thought that the only way
to act on the brain is by giving external compounds” said Sale. “We think that a proper
optimisation of environmental stimuli can drive the brain to endogenously produce substances
able to enhance neuronal plasticity. This brain self-recovery based treatment is completely noninvasive, without collateral effects and risks.”
“The non-invasiveness of environmental manipulation makes this practice particularly suitable
for application in humans,” commented Dr Sale. “Studies running in our lab demonstrate that
environmental enrichment is not only able to promote vision recovery in amblyopic subjects, but
may also enhance cognitive functions in patients with Down syndrome, or at early stages of
Alzheimer’s disease.”
END
Abstract Reference R10204: Environmental enrichment and enviromimetics: impact on visual
cortex plasticity
Symposia S36: Adult cortical plasticity
Contact
FENS Press Office and all media enquiries:
Elaine Snell, Snell Communications Ltd, London UK (English language)
tel: +44 (0)20 7738 0424 or mobile +44 (0)7973 953 794
email: Elaine@snell-communications.net
Mauro Scanu (Italian language)
tel: +39 333 161 5477
email: press.office@fens.org
Dr Alessandro Sale alessandro.sale@in.cnr.it
NOTES TO EDITORS
The 9th FENS Forum of Neuroscience, the largest basic neuroscience meeting in Europe,
organised by FENS and hosted by the The Società Italiana di Neuroscienze (SINS) (Italian
Society for Neuroscience) will attract an estimated 5,500 international delegates. The
Federation of European Neuroscience Societies (FENS), founded in 1998, aims to advance
research and education in neuroscience, representing neuroscience research in the European
Commission and other granting bodies. FENS represents 42 national and mono-disciplinary
neuroscience societies with close to 23,000 member scientists from 32 European countries.
http://fens2014.neurosciences.asso.fr/