Hunger-Dependent Enhancement of Food Cue Responses in Mouse Postrhinal Cortex and Lateral Amygdala

Abstract

Summary The needs of the body can direct behavioral and neural processing towards motivationally relevant sensory cues. For example, human imaging studies have consistently found specific cortical areas with biased responses to food-associated visual cues in hungry subjects, but not in sated subjects. To obtain a cellular-level understanding of these hunger-dependent cortical response biases, we performed chronic two-photon calcium imaging in postrhinal association cortex (POR) and primary visual cortex (V1) of behaving mice. As in humans, neurons in mouse POR, but not V1, exhibited biases towards food-associated cues that were abolished by satiety. This emergent bias was mirrored by the innervation pattern of amygdalo-cortical feedback axons. Strikingly, these axons exhibited even stronger food cue biases and sensitivity to hunger state and trial history. These findings highlight a direct pathway by which the lateral amygdala may contribute to state-dependent cortical processing of motivationally relevant sensory cues.

Homeostatic circuits selectively gate food cue responses in insular cortex

“…AgRP activation during satiety was sufficient to restore InsCtx response patterns, such that food availability information could potentially be read out by downstream neurons. Consistent with results from other cortical regions 16,26 , InsCtx preserves stable population response properties, despite variability in the average responses of individual neurons across days.…”

“…2e). In contrast, early visual cortex responses were not substantially modulated by hunger using the identical experimental setup 16 , arguing against global arousal driving InsCtx hunger modulation. To confirm this, we used moment-to-moment changes in pupil diameter as a proxy for changes in arousal 22 ( n = 266 neurons, three additional mice; Fig.…”

“…3a–d). Cue responses did not show systematic attenuation across a session, although trial-to-trial response variability was higher than in visual cortical areas 16 (Extended Data Fig. 3e, f).…”

“…We trained food-restricted mice to perform a go/no-go visual discrimination task in which licking after different learned visual cues led to delivery of liquid food (Ensure), aversive bitter solution (quinine), or no outcome 16 (Fig. 1a).…”

“…BLA encodes the value of learned cues 12,16,30,31 , and is necessary for InsCtx responses to these cues 12 . BLA neurons that project to nucleus accumbens (NAc) and central amygdala (CeA) are important for behaviours involving cues predicting reward and punishment 32–34 .…”