LTP in the barrel cortex of adult rats.

Intrinsic circuitry in the barrel cortex has been shown to be readily modifiable in response to changes in the patterns of sensory input, even in adult animals. It is believed that sensory experience modifies synaptic circuits by imposing specific patterns of repetitive presynaptic and postsynaptic coactivity, i.e. by LTP-like processes. However, the ability of intrinsic cynapses in the adult barrel cortex to express LTP has not been demonstrated. In slices from barrel cortex of adult rats, we show that input-specific LTP can be induced in the supragranular layers by tetanic stimulation of intracortical vertical and horizontal inputs.