Bidirectional activity-dependent plasticity at corticostriatal synapses.

@article{citeulike:467152, abstract = {Corticostriatal projections originate from the entire cerebral cortex and provide the major source of glutamatergic inputs to the basal ganglia. Despite the importance of corticostriatal connections in sensorimotor learning and cognitive functions, plasticity forms at these synapses remain strongly debated. Using a corticostriatal slice preserving the connections between the somatosensory cortex and the target striatal cells, we report the induction of both non-Hebbian and Hebbian forms of long-term potentiation (LTP) and long-term depression (LTD) on striatal output neurons (SONs). LTP and LTD can be induced selectively by different stimulation patterns (high-frequency trains vs low-frequency pulses) and were evoked with similar efficiency in non-Hebbian and Hebbian modes. Combination of LTP-LTD and LTD-LTP sequences revealed that bidirectional plasticity occurs at the same SONs and provides efficient homeostatic mechanisms leading to a resetting of corticostriatal synapses avoiding synaptic saturation. The effect of temporal relationship between cortical stimulation and SON activity was assessed using spike-timing-dependent plasticity (STDP) protocols. An LTP was observed when an action potential was triggered in the striatal neuron before the cortical stimulus, and, conversely, an LTD was induced when the striatal neuron discharge was triggered after the cortical stimulation. Such STDP was reversed when compared with those described so far in other mammalian brain structures. This mechanism may be essential for the role of the striatum in learning of motor sequences in which sensory and motor events are associated in a precise time sequence.}, address = {Dynamique et Physiopathologie des R\'{e}seaux Neuronaux, Institut National de la Sant\'{e} et de la Recherche M\'{e}dicale (INSERM) U-667, Coll\`{e}ge de France, 75231 Paris Cedex 05, France.}, author = {Fino, E. and Glowinski, J. and Venance, L. }, citeulike-article-id = {467152}, doi = {10.1523/JNEUROSCI.4476-05.2005}, issn = {1529-2401}, journal = {J Neurosci}, keywords = {cortex, ltd, ltp, medium-spiny-neurons, plasticity, stdp}, month = {December}, number = {49}, pages = {11279--11287}, posted-at = {2007-03-29 11:29:07}, priority = {0}, title = {Bidirectional activity-dependent plasticity at corticostriatal synapses.}, url = {http://dx.doi.org/10.1523/JNEUROSCI.4476-05.2005}, volume = {25}, year = {2005} }

TY - JOUR ID - citeulike:467152 L3 - citeulike-article-id:467152 TI - Bidirectional activity-dependent plasticity at corticostriatal synapses. JF - J Neurosci VL - 25 IS - 49 SP - 11279 EP - 11287 AD - Dynamique et Physiopathologie des Réseaux Neuronaux, Institut National de la Santé et de la Recherche Médicale (INSERM) U-667, Collège de France, 75231 Paris Cedex 05, France. SN - 1529-2401 N2 - Corticostriatal projections originate from the entire cerebral cortex and provide the major source of glutamatergic inputs to the basal ganglia. Despite the importance of corticostriatal connections in sensorimotor learning and cognitive functions, plasticity forms at these synapses remain strongly debated. Using a corticostriatal slice preserving the connections between the somatosensory cortex and the target striatal cells, we report the induction of both non-Hebbian and Hebbian forms of long-term potentiation (LTP) and long-term depression (LTD) on striatal output neurons (SONs). LTP and LTD can be induced selectively by different stimulation patterns (high-frequency trains vs low-frequency pulses) and were evoked with similar efficiency in non-Hebbian and Hebbian modes. Combination of LTP-LTD and LTD-LTP sequences revealed that bidirectional plasticity occurs at the same SONs and provides efficient homeostatic mechanisms leading to a resetting of corticostriatal synapses avoiding synaptic saturation. The effect of temporal relationship between cortical stimulation and SON activity was assessed using spike-timing-dependent plasticity (STDP) protocols. An LTP was observed when an action potential was triggered in the striatal neuron before the cortical stimulus, and, conversely, an LTD was induced when the striatal neuron discharge was triggered after the cortical stimulation. Such STDP was reversed when compared with those described so far in other mammalian brain structures. This mechanism may be essential for the role of the striatum in learning of motor sequences in which sensory and motor events are associated in a precise time sequence. KW - cortex KW - ltd KW - ltp KW - medium-spiny-neurons KW - plasticity KW - stdp AU - Fino, E AU - Glowinski, J AU - Venance, L PY - 2005/12/07/ UR - http://dx.doi.org/10.1523/JNEUROSCI.4476-05.2005 ER -