The Michelin red guide of the brain: Role of dopamine in goal-oriented navigation

1. Front Syst Neurosci. 2014 Mar 18;8:32. doi: 10.3389/fnsys.2014.00032. eCollection
2014.

The Michelin red guide of the brain: role of dopamine in goal-oriented
navigation.

Retailleau A(1), Boraud T(2).

Author information:
(1)Sagol Department of Neurobiology, University of Haifa Haifa, Israel.
(2)Institut des Maladies Neurodegeneratives UMR 5293, University of Bordeaux
Bordeaux, France ; Institut des Maladies Neurodegeneratives UMR 5293, CNRS
Bordeaux, France.

Spatial learning has been recognized over the years to be under the control of
the hippocampus and related temporal lobe structures. Hippocampal damage often
causes severe impairments in the ability to learn and remember a location in
space defined by distal visual cues. Such cognitive disabilities are found in
Parkinsonian patients. We recently investigated the role of dopamine in
navigation in the 6-Hydroxy-dopamine (6-OHDA) rat, a model of Parkinson’s disease
(PD) commonly used to investigate the pathophysiology of dopamine depletion
(Retailleau et al., 2013). We demonstrated that dopamine (DA) is essential to
spatial learning as its depletion results in spatial impairments. Our results
showed that the behavioral effect of DA depletion is correlated with modification
of the neural encoding of spatial features and decision making processes in
hippocampus. However, the origin of these alterations in the neural processing of
the spatial information needs to be clarified. It could result from a local
effect: dopamine depletion disturbs directly the processing of relevant spatial
information at hippocampal level. Alternatively, it could result from a more
distributed network effect: dopamine depletion elsewhere in the brain (entorhinal
cortex, striatum, etc.) modifies the way hippocampus processes spatial
information. Recent experimental evidence in rodents, demonstrated indeed, that
other brain areas are involved in the acquisition of spatial information. Amongst
these, the cortex-basal ganglia (BG) loop is known to be involved in
reinforcement learning and has been identified as an important contributor to
spatial learning. In particular, it has been shown that altered activity of the
BG striatal complex can impair the ability to perform spatial learning tasks. The
present review provides a glimpse of the findings obtained over the past decade
that support a dialog between these two structures during spatial learning under
DA control.

DOI: 10.3389/fnsys.2014.00032
PMCID: PMC3957057
PMID: 24672436

Auteurs Bordeaux Neurocampus