Simplify the following text for a Grade 12 native English-speaking person.
Original: Another symptom of mania is racing thoughts during which the sufferer is excessively distracted by unimportant stimuli .
Simplified: One of the most signature symptoms of mania ( and to a lesser extent , hypomania ) is what many have described as racing thoughts . These are usually instances in which the manic person is excessively distracted by objectively unimportant stimuli .