Cingulate-Hippocampus Coherence and Trajectory Coding in a Sequential Choice Task

• Published in: Neuron (Cambridge, Mass.) Mass.), 2013-12, Vol.80 (5), p.1277-1289
• Main Authors: Remondes, Miguel, Wilson, Matthew A.
• Format: Article
• Language: English
• Subjects: Action Potentials - physiology; Animals; Association Learning - physiology; Bayes Theorem; Behavior; Choice Behavior - physiology; Gyrus Cinguli - physiology; Hippocampus - physiology; Hypotheses; Male; Neural Pathways - physiology; Neurons; Neurons - physiology; Rats; Rats, Long-Evans; Spectrum Analysis; Studies; Theta Rhythm
• ISSN: 0896-6273; 1097-4199
• DOI: 10.1016/j.neuron.2013.08.037

Interactions between cortex and hippocampus are believed to play a role in the acquisition and maintenance of memories. Distinct types of coordinated oscillatory activity, namely at theta frequency, are hypothesized to regulate information processing in these structures. We investigated how information processing in cingulate cortex and hippocampus relates to cingulate-hippocampus coordination in a behavioral task in which rats choose from four possible trajectories according to a sequence. We found that the accuracy with which cingulate and hippocampal populations encode individual trajectories changes with the pattern of cingulate-hippocampal theta coherence over the course of a trial. Initial theta coherence at ∼8 Hz during trial onsets lowers by ∼1 Hz as animals enter decision stages. At these stages, hippocampus precedes cingulate in processing increased amounts of task-relevant information. We hypothesize that lower theta frequency coordinates the integration of hippocampal contextual information by cingulate neuronal populations, to inform choices in a task-phase-dependent manner. [Display omitted] •Theta oscillations coordinate cingulate cortex and hippocampus in a decision task•Cingulate and hippocampal neurons accurately encode individual trajectories•Decreasing frequency of theta coherence underlies increasing trajectory information•At decision stages, hippocampal spikes precede cingulate spikes and LFP Remondes and Wilson recorded brain activity in rats during a sequential trajectory choice task. They identified a potential mechanism by which distinct theta oscillations support the transfer of spatial information from hippocampus to cingulate cortex to guide trajectory choices.