A new electrophysiological study in rodents demonstrates that taste-odor convergence occurs in posterior piriform olfactory cortex and calls for a reformulation of classic models of the central representation of flavor.

The deep piriform region has an unusually high seizure susceptibility. Voltage imaging previously located the sites of epileptiform discharge onset in slices of rat piriform cortex and revealed the spatiotemporal pattern of development of two types of electrical activity during the latent period prior to discharge onset. A ramplike depolarization (onset activity) appears at the site of discharg...

Recurrent intracortical connections are believed to be especially dense in the piriform cortex. Two studies in this issue of Neuron report several interesting features of the long-range intracortical connections and reveal their physiological roles in shaping olfactory processing.

Paradoxically, attempts to visualize odorant-induced functional magnetic resonance imaging (fMRI) activation in the human have yielded activations in secondary olfactory regions but not in the primary olfactory cortex-piriform cortex. We show that odorant-induced activation in primary olfactory cortex was not previously made evident with fMRI because of the unique time course of activity in thi...

Dopaminergic Modulation of Entorhinal Cortex Function Douglas A. Caruana, Ph.D. Concordia University, 2008 The neurotransmitter dopamine has been shown to play an important role in the mnemonic functions of the prefrontal cortex, but it is unclear how dopamine may affect sensory and mnemonic processing in the entorhinal cortex. Midbrain dopamine neurons project to the superficial layers of the ...

The piriform cortex (PCX) is the largest component of the olfactory cortex and is hypothesized to be the locus of odor object formation. The distributed odorant representation found in PCX contrasts sharply with the topographical representation seen in other primary sensory cortices, making it difficult to test this view. Recent work in PCX has focused on functional characteristics of these dis...