Migratory birds experience differences in the amount and quality of sleep they get during different seasons. Ruth Benca and her colleagues from the University of Wisconsin-Madison have now shown that they also have decreased impulse control whilst in their migratory state.
Benca’s team has been studying the White-crowned Sparrow. This small bird spends 60% less time sleeping while migrating than at other times. Some specimens have been known to stay awake for up to two straight weeks. Nonetheless, it is capable of learning new behaviors, such as pecking a button to receive food, during periods of sleep deprivation. In contrast, during the migratory time period, it’s much more difficult for the birds to learn not to peck at a button, or not to perform some other action. They seem to have a decreased ability to withhold a response.
The scientists aren’t sure what is causing the loss of behavioral inhibition. It doesn’t appear to be purely a symptom of sleep deprivation because other types of learned behavior are not diminished.
As Benca states:
Whether the inability to inhibit pecking is related to a general failure of inhibition, a distorted sense of time, inattention to salient cues, or some other underlying mechanism is not entirely clear.