Volume 7 Issue 7, July 2004

In a brainstem auditory nucleus, excitatory synapses from the same presynaptic neuron are shown to cause opposing forms of spike timing–dependent plasticity in projection neurons and GABAergic interneurons at low frequencies, but to cause the same form of plasticity at high frequencies. The net effect is to enhance activation of the projection neurons by relevant stimuli.

Olfactory neurons adapt to prolonged odor exposure through calcium-calmodulin inhibition of cyclic nucleotide-gated channels. A study in this issue reveals a new mechanism for olfactory adaptation under native conditions, via unexpected binding sites.

Neurons adapt to sustained alterations in activity by changing their intrinsic excitability. A form of this plasticity in hippocampal pyramidal neurons involves calcineurin-dependent dispersion and change in gating of K⁺ channels, reducing the cell's excitability.

The ventral visual stream is proposed to support perception, and the dorsal stream is proposed to control action. A new study of patients with posterior parietal damage shows that the dorsal stream also contributes to automatic obstacle avoidance in reaching.