The aim of the current study was to evaluate arousal modulation and response inhibition in adults with high functioning autism (HFA). Using a go/no-go paradigm with varying presentation rate, it was found that performance efficiency (Mean RT, Standard Deviation of RT and Errors of Commission) in adults with HFA was the same as in the control group in the condition with a slow (6 s) and medium (2 s) presentation rate, but that it decreased in the condition with a fast presentation rate (1 s): many errors of commission were made in this condition. Findings were interpreted in terms of an arousal modulation deficiency that interfered with the capacity to inhibit responses in HFA.