Summary
The amygdala is a part of the brain that helps us experience fear. A disease called Urbach-Wiethe disease destroys the amygdala, and people with that disease don’t usually experience fear. However, some people, including people with the disease, experience fear when they breath in a lot of carbon dioxide.
Strongly Supported Conclusions
The stimulus supports these inferences:
The amygdala is not necessary for every experience of fear.
Thus, there must be other parts of the brain that can also sense fear.
In particular, the amygdala is not necessary to experience fear caused by breathing in carbon dioxide.
The amygdala is not necessary for every experience of fear.
Thus, there must be other parts of the brain that can also sense fear.
In particular, the amygdala is not necessary to experience fear caused by breathing in carbon dioxide.
A
Extreme fear is not the only intense response that people can have to a breath that is high in carbon dioxide.
This is not supported. All we know about people’s response to taking a breath high in carbon dioxide is that it can cause extreme fear. Maybe it can cause other responses too, but we don’t know that.
B
Sensing fear is not the only function the amygdala can serve.
This is not supported. The stimulus just tells us that the amygdala is involved in sensing fear. We have no information about whether or not it does anything else.
C
Urbach-Wiethe disease is not the only disease that can destroy the amygdala.
This is not supported. Just because Urbach-Wiethe disease destroys the amygdala, that doesn’t imply that it’s the only disease which destroys the amygdala. To say so, we would need further information (which we don’t have).
D
The amygdala is not the only part of the brain that can be affected by Urbach-Wiethe disease.
This is not supported. We don’t know anything about Urbach-Wiethe disease except that it affects the amygdala. It’s possible that it affects other brain areas too, and equally possible that it doesn’t. We just don’t know.
E
The amygdala is not the only part of the brain that can be involved in sensing fear.
This is strongly supported. When people with Urbach-Wiethe disease experience fear from breathing carbon dioxide, their amygdala can’t be responsible, because it’s been destroyed. That must mean some other part of the brain senses that particular fear.