Volume 8 Issue 7, July 2005

Long-term potentiation and long-term depression require postsynaptic depolarization, which many current models attribute to backpropagating action potentials. New experimental work suggests, however, that other mechanisms can lead to dendritic depolarization, and that backpropagating action potentials may be neither necessary nor sufficient for synaptic plasticity in vivo.

Empathy refers to our ability to share emotions and sensations such as pain with others. Imaging studies on pain showed that the affective but not sensory component of our pain experience is involved in empathy for pain. In contrast, a new study using transcranial magnetic stimulation highlights for the first time the role of sensorimotor components in empathy for pain in other people.

The rodent brain constantly generates new granule and periglomerular interneurons to replenish the olfactory bulb. New work shows that the two subtypes are derived from distinct progenitor populations, revealing unexpected diversity among adult neural stem cells.

The postsynaptic protein GRIP1 is now shown to work with the receptor tyrosine kinase EphB2 to bind a kinesin microtubule motor protein. This causes dendritic transport of EphB2, triggering a pathway critical for establishment and maintenance of dendritic arbors.

Illusions of spatial vision can occur during rapid eye movements known as saccades. A new report shows that temporal judgments are also distorted around the time of saccades, suggesting that the neural representations of time and space may be linked.

Although we hear sounds throughout their duration, studies on anesthetized animals have suggested that auditory cortex neurons primarily detect changes in sound. New evidence in a report in Nature from awake animals is forcing us to reconsider this view.