Steele Lab

The neurobiology of food anticipation

The saying goes that the "early bird catches the worm", but how does the bird know when to wake up? Our laboratory has been trying to crack this question for the past 8 years. Researchers in the field of circadian rhythms have coined the term "food anticipatory activity" to describe the phenomenon that animals will show activity and wakefulness in anticipation of scheduled meals--even when those meals occur during a time of day when they would normally be asleep. Neural circuit level understanding of food anticipatory activity is at a primitive stage. The work of our laboratory has implicated the dopamine neuromodulatory system as a mediatior of food anticipatory activity but there's much work to be done in order to shore up these findings. Here's our understanding of how dopamine signaling helps us to tell time relative to feeding:

--Dopamine signaling to type 1 dopamine receptors (D1r) is important for behavioral arousal in anticipation of scheduled calorie restricted meal time

--Mice with dopamine expression only in their dorsolateral striatum (and no where else) show food anticipatory activity

--Daily, timed activation of D1r neurons using a drug leads to anticipatory activity even in mice that are not food restricted

--Food timing appears to be independent of the dopamine transporter (Slc6a3)

--Food timing also appears to be independent of Pitx3-expressing dopamine neurons