{'fraction_non_alphanumeric': 0.014319809069212411, 'fraction_numerical': 0.00477326968973747, 'mean_word_length': 4.7465753424657535, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Effects of age, brain damage, and task complexity on the sensitivity of reaction time to the delay between the warning signal and the stimulus.

Four age groups of normal subjects were given a visual reaction time task with three levels of uncertainty. The speed of response improved when the interval between the auditory warning signal and the imperative visual stimulus increased in the range from 1 to 3 s. This delay effect decreased when the level of uncertainty was increased, irrespective of the age. This phenomenon was globally reiterated in two control experiments. A set of 21 brain-injured subjects with clinical complaints concerning attention was also given the test. These subjects were also able to benefit from the delay. The benefit was affected neither by the task complexity nor by the slowness of the reaction times.