The gut-brain connection is mostly known for its role in controlling the amount of food we eat, with the gut signaling to the brain when we’ve had enough. But a new study published on June 5 in a journal suggests that the gut-brain connection may also play an important role in forming memories about where places and objects are located in our environment. The new study was done in rats, but the findings could translate to humans.
The gut and the brain mainly communicate through the vagus(迷走神经)nerve. Because this gut-brain axis is typically engaged only when an animal is eating, the researchers thought that this function could serve animals in remembering where good food was in their environment. This could be important for the animals to remember where they were, so that they could find that food again. Researchers set up several tasks that challenged the rats to find and remember either locations or objects around them. In one experiment, for example, the researchers shone a bright light that would be annoying enough to lead a rat to search for an escape. With a complete vagus nerve, the rats were able to remember where the location was if they’d previously found it and gone there.
But if the gut-brain connection was surgically altered, the rats had trouble remembering where an escape location was, even though they had previously been there, the researchers found. Similarly, when the scientists had the rats try to find objects that the animals had previously located, they had difficulty if their vagus nerve was blocked from sending signals.
When the researchers looked at the brains of the rats that had altered vagus nerves, they found that there was decreased activity in the hippocampus, an area of the brain involved with specific types of memory. That includes helping the animal figure out its own position and that of other rats and objects. Specifically, the rats had decreased numbers of several proteins in the hippocampus that are responsible for creating new neurons(神经元)and connections between neurons. These proteins therefore also play a role in forming memories.
23. What does the new study published on June 5 find?
A.The gut-brain connection communicates through vagus nerves. |
B.The gut-brain connection helps you remember where you had a good meal. |
C.The gut-brain connection helps you remember you really had a good meal. |
D.The gut-brain connection translates to humans. |
24. Why is a bright light used?
A.To force a rat to find a way out. |
B.To frighten a rat to eat less food. |
C.To scare a rat to forget the location. |
D.To help a rat remember the objects. |
25. Which of the following best explains “altered” underlined in paragraph 3?
A.Connected. | B.Changed. |
C.Located. | D.Found. |
26. Which of the following are responsible for forming memories?
A.Guts. | B.Hippocampus. |
C.Vagus nerves. | D.New neurons. |