LAUSR

Neuroscience All living reptiles and mammals have a brain cortex derived from a common primordial cortex. Thus, they may retain traces of this common ancestry in their structure, connectivity, and function. Hemberger et al. simultaneously sampled action potentials from hundreds of neurons in intact turtle cortical explants and found that minimal manipulation of single cortical pyramidal cells had detectable effects on other neurons and on the animal's behavior. With only one to three spikes, single pyramidal neurons could trigger distributed patterns of firing that cascaded across neurons, space, and time in the form of reliable firing sequences. These sequences are similar to those produced during replay events in the mammalian hippocampus. These data provide evidence for chained synaptic activation in a cortical structure supporting the synfire chain hypothesis. Neuron 10.1016/j.neuron.2019.07.017 (2019).