This study investigated the premise that disordered temporal order perception in retarded readers can be seen in the serial processing of both nonverbal auditory and visual information, and examined whether such information processing deficits relate to level of reading ability. The adult subjects included 20 in the dyslexic group, 12 in the reading disabled group, and 20 in the control group. Findings indicated that deficient readers, as a group, exhibited significant deficiencies in the temporal sequencing of nonverbal information. The study suggests that the part of the brain most critically involved in ordering and timing the units of perception as well as behavior is that of the left prefrontal cortex, and that the major role of this timing mechanism is to organize the structural units of language and to encode these for purposes of recall, recognition, and action. (DB)