Vanishing dual-task interference after practice: has the bottleneck been eliminated or is it merely latent?
Practice can, in some cases, largely eliminate measured dual-task interference. Does this absence of interference indicate the absence of a processing bottleneck (defined as an inability to carry out certain stages in parallel)? The authors show that a bottleneck need not produce any observable interference, provided that there is no temporal overlap in the demand for bottleneck stages on the 2 tasks. Such a "latent" bottleneck is especially likely after practice, when central stages are short. The authors provide new evidence that a latent bottleneck occurred for a participant who produced no interference in M. Van Selst, E. Ruthruff, and J. C. Johnston (1999). These findings demonstrate that the absence of dual-task interference does not necessarily indicate the absence of a processing bottleneck.
Ruthruff
Eric
E
National Aeronautics and Space Administration, Ames Research Center, Moffett Field, California 94035, USA. eruthruff@mail.arc.nasa.gov
Johnston
James C
JC
Van Selst
Mark
M
Whitsell
Shelly
S
Remington
Roger
R
D001288:Attention; D005364:Field Dependence-Independence; D005500:Follow-Up Studies; D006801:Humans; D008606:Mental Processes / Q000502:physiology*; D010363:Pattern Recognition, Automated; D010470:Perceptual Masking / Q000502:physiology*; D010898:Pitch Perception / Q000502:physiology; D011214:Practice, Psychological; D011340:Problem Solving / Q000502:physiology; D011582:Psychological Theory; D011930:Reaction Time / Q000502:physiology*; D012033:Refractory Period, Psychological / Q000502:physiology; D014796:Visual Perception / Q000502:physiology