Effects of Response Complexity upon Listening to Competing Messages

Three groups of twelve men listened to sequences of two, three, or four competing messages. They listened under four different conditions, two conditions of filtering (filters in—filters out) and two conditions of spatial separation (channels split—channels together). They responded on certain occasions to one message of the set and at other times to two messages. The first group wrote down, in simple symbols, the content of the message (s) whose address(es) they were to guard. The second group spoke the content of the assigned messages to a partner who wrote it down. The third group transposed (decoded) the message content before writing it down. The results show that (1) more than twice as many errors occurred when responding to two instead of one message, (2) whether responding to one or two messages, transposing or talking produced an increase frequency of errors of 10% over writing, and (3) errors increased as the listening condition changed from Filtered-Split to Unfiltered-Split to Filtered-Together to Unfiltered-Together.