New research sheds light on why it feels harder to wake up in cold winter mornings

Scientists have discovered a neuronal circuit in flies that acts like a thermometer, inhibiting neurons responsible for alertness, especially in the morning. Researchers from Northwestern University found that receptors in the fly's antennas respond to temperatures below 25°C (77°F). These receptors communicate with brain neurons that regulate wakefulness and sleep rhythms. When external temperatures drop, neurons usually activated by morning light are suppressed, affecting the fly's alertness.

What have scientists identified in a fly's brain that affects alertness?

• A pressure-sensitive circuit of neurons

• A thermometer-like circuit of neurons

• A light-sensitive circuit of neurons

• A sound-sensitive circuit of neurons

Which university's neurobiologists found receptors in the fly's antennas?

• Harvard University

• Northwestern University

• Stanford University

• MIT

At what temperature do the receptors in the fly's antennas respond?

• Above 77 degrees Fahrenheit

• Exactly 25 degrees Celsius

• Below 25 degrees Celsius

• Above 30 degrees Celsius

What is the role of the larger circuit of brain cells in flies?

• Regulating wakefulness and sleep rhythms

• Controlling flight patterns

• Managing mating behaviors

• Regulating feeding habits

What happens to neurons activated by morning light when the circuit is triggered by lower temperatures?

• They become more active

• They shut down

• They change their function

• They increase in number