Science Briefs

Picking Up the Check When it's Time to Pay Attention

With support from the National Institute of Child Health and Human Development, we have been studying the nature and development of attention in monkeys and humans, using game-like computer tasks like those referenced above to identify what attention is, how it is controlled, and how to improve its effectiveness.

By David A. Washburn, PhD

The air fills with characteristic tones and tunes that accompany the newest computer game. The screen sparkles with colorful graphics and action. A hand deftly controls a joystick. Eyes remain transfixed on the display. Minutes pass. Hours pass. Oblivious to the rest of the world, all attention is directed to the task of completing the next level or setting the high score.

It is a scene repeated daily in bedrooms or game-rooms across the country. In this particular instance, however, the location is a laboratory at Georgia State University's Language Research Center rather than a home; and the hand on the joystick belongs to a rhesus monkey, not a person.

Almost to the day, it has been 20 years since we discovered that rhesus monkeys (Macaca mulatta) and other nonhuman primates could learn to manipulate a joystick in game-like computerized tasks so as to respond skillfully to computer-generated stimuli (Rumbaugh, Richardson, Washburn, Savage-Rumbaugh, & Hopkins, 1987; Savage-Rumbaugh, 1986). At our laboratory and dozens of others, many of the classic tests from comparative psychology, cognitive psychology, developmental psychology, and neuropsychology have been translated into computer programs--much as has become common in research with humans--that look like simple video games. Although Sony and Nintendo will never fear the graphics and complexity of these games, monkeys and apes find the tasks to be highly motivating and enriching. Our monkeys have continuous access to the computerized tasks, and thus can work whenever they want or rest whenever they want. In doing so, they control their intake of fruit-flavored chow pellets, although they receive food freely whether or not they engage the tasks, and are never reduced in body weight or food-deprived for purposes of testing. Perhaps more importantly, the animals can in this way control their level of stimulation, challenge, and activity. These game-like computer tasks provide a significant means for promoting and assessing the psychological well-being of the nonhuman primates (Washburn, 2003, Washburn & Rumbaugh, 1992), and the monkeys (like many humans) spend many hours each day in rapt attention to the tasks.

The Control of Attention

But what does this say about the nature of attention itself? Monkeys and children are engrossed by television and computer games, but some of these same children struggle to pay attention in other contexts, like school. Is an organism's capacity for attention better characterized by these inattentive instances or by those hours in which attention is captivated by entertainment?

With support from the National Institute of Child Health and Human Development, we have been studying the nature and development of attention in monkeys and humans, using game-like computer tasks like those referenced above to identify what attention is, how it is controlled, and how to improve its effectiveness. The term attention describes a collection of cognitive processes involved in the orientation to and selection of particular stimuli or responses to process, the concentration or mental effort dedicated to this processing, and the state of alertness or readiness to process additional stimuli. Evidence from experimental studies, psychometric studies (e.g., Mirsky, Pascualvaca, Duncan & French, 1999; Stankov, 1988), and neuroscientific studies using fMRI (Fan, McCandliss, Fossella, Flombaum, & Posner, 2005; Posner & Raichle, 1994) reveals the construct of attention to be comprised of separate factors or subsystems (e.g., attention focusing, attention scanning, attention sustaining) that are associated with distinct brain networks (e.g., an executive attention network, including prefrontal brain regions and particularly the anterior cingulate gyrus; an alerting network involving the coordination of temporal and parietal regions of the right hemisphere) and neurotransmitter systems.

Our research with monkeys has targeted the question of what determines, on a moment-by-moment basis, what an organism will attend to (as reflected in its behavior). We have found that the control of attention is competitively determined, a result of the constant battle that exists between what we term

Environmental constraints on attention: sudden changes in stimuli, movement, and novelty elicit a capture of attention

Experiential constraints on attention: conditioning (habits) and priming exert stimulus-control over attention

Executive constraints on attention: intentions, instructions, and goals exert endogenous control over the locus and intensity of attention

In other words, what we attend to at any moment depends on the relative potency of the stimuli in the environment, the strength of our associative history with those stimuli, and the capacity we have at that moment for over-ruling these exogenous influences by volition (see Washburn & Taglialatela, 2006). What appears to distinguish monkeys from humans with respect to attention is NOT that humans have attention and monkeys do not--monkeys certainly can and do evidence attention in virtually every familiar task used to study the construct (e.g., visual search, Stroop, cuing and anti-saccade tasks, dual-task performance). Rather, it appears that, relative to typical humans, monkeys are much less effective in resisting strong environmental or experiential cues in favor of executive constraints on attention. Even when incentives and instructions dictate that a monkey should maintain its focus, these animals are easily distracted by stimuli that suddenly appear in the environment or that are prepotent by virtue of an extensive reward history for the animals. In contrast, most humans, when they are really motivated, are relatively better at resisting distraction and staying on task.

Consider the Stroop task, in which one must name the color in which a word is printed and ignore the meaning of the word, which itself may be the name of a color that is congruous (the word "BLUE" printed in blue) or incongruous (the word "RED" printed in blue) with the response (which is "blue" in both of these examples). Executive constraints, dictated by the task instructions, are to report the word color, but strong experiential constraints (the strong habit of reading the word) compete with these responses. Human adults and children show characteristic effects under these conditions: responses are slower and frequently less accurate on incongruous trials than on congruous trials. Tested on a version of this task, rhesus monkeys also show this Stroop effect; however, the magnitude of the interference by the incongruous condition is much greater for monkeys than for humans (Washburn, 1994). One can further manipulate the potency of these competing constraints, such as by varying the proportion of congruent (Kane & Engle, 2004). The greater the proportion of congruent trials, the more the habit of reading the word is reinforced; the greater the proportion of incongruent trials, the more the executive constraints are emphasized. Responses by monkeys to their version of this task show big effects of making the experiential constraints more potent; however, monkeys benefit significantly less than do humans from manipulations that strengthen the cues for executive attention in this task.

The attentive monkey, the attentive child

Relative to humans, it is not that monkeys have less attention but rather that they have less executive control over attention. This is significant because it suggests the hypothesis that relative to adults, it is not that children have less attention but rather that they have less executive control over attention. Relative to typical populations, it is not that individuals with attention deficits have less attention (or broken attention) but rather that they have less executive control over attention. These potential parallels raise an intriguing question: Can the capacity for executive-attention by monkeys be improved with particular types of practice or instruction?

Monkeys do not naturally attend to boring things. If a stimulus does not capture attention by means of novelty or suddenness, or if the stimulus is not strongly associated with food, threat, pleasure, and so forth, a monkey is disinclined to attend to it. However, we have seen improvements in our monkeys' vigilance even to boring tasks with their computerized test-system experience. We are attempting to identify the conditions under which the monkeys will become more resistant to stimulus cues and more capable of executive attention.

In a parallel project, Mary Rothbart, Michael Posner, and their collaborators at the University of Oregon have been examining the development of executive attention in young children. A volume, Educating the Human Brain, based on this work will be published by APA books this fall. With initial funding from the McDonnell Foundation and NIMH, these scientists developed a series of computer exercises for toddlers, modeled after the tasks we used to train rhesus monkeys (Rumbaugh et al., 1987; Washburn, 2003). They have recently published results of attention training for 4- and 6-year-old children (Rueda, Rothbart, Saccamanno, & Posner, 2005). They found that a brief five day training showed positive gains in executive attention, IQ and in the underlying executive attention network as recorded from scalp electrodes. The programs are freely available on the web at www.teach-the-brain.org. These investigators are currently working with others to test these ideas, introducing the activities to additional normal children as well as those suffering from disorders that, like ADHD and Autism, involve attentional networks.

Together with Brad Sheese, Rothbart and Posner are also conducting a longitudinal study, from age 7 months to 4 years of age, to determine the origins of executive attention in infancy. Preliminary results suggest a connection between executive attention and anticipatory eye movements found when infants are presented a series of stimuli in fixed locations on a computer screen. The attention training studies showed vast individual differences among even young children in the ability to control their attention. Evidence for the involvement of dopamine genes in these differences is being followed up in the current longitudinal study. The eye movement and genetic studies provide means to further the connections between human and monkey research.

This type of collaboration, in which findings from research with nonhuman animals produce principles that may be applied to improving child health and human development, follows a formula for success established decades ago. Then, it was language research with chimpanzees and bonobos at the Language Research Center that generated fundamental knowledge about what language is and how it could be learned by animals that do not naturally demonstrate such competencies (Rumbaugh & Washburn, 2003; Savage-Rumbaugh, 1986). This knowledge in turn was applied with outstanding results to interventions with nonspeaking human children with mental retardation (Romski, 1989; Romski & Sevcik, 1996).

Even as these ape-language studies continue at the Language Research Center, our hope is that the present research will continue to be successful in gleaning knowledge from a species that does not readily show executive attention and applying that knowledge to human children and adults who may also struggle in this area.

Acknowledgments

This research is supported at Georgia State University and the University of Oregon by the grant HD-38051 from the National Institutes of Child Health and Human Development. Additional support for this project has been provided by the McDonnell-Pew Foundation, the National Aeronautics and Space Administration, National Institute of Mental Health, and by Georgia State University. Tom Putney, Sandy Kleinman, Kimberly Espy, Duane Rumbaugh, and a host of outstanding graduate assistants contribute richly to the success of this research.

References

Fan, J., McCandliss, B.D., Fossella, J., Flombaum, J.I., & Posner, M.I. (2005) The activation of attentional networks Neuroimage 26:471-9

Kane, M. J., & Engle, R. W. (2003). Working-memory capacity and the control of attention: The contributions of goal neglect, response competition, and task set to Stroop interference. Journal of Experimental Psychology: General, 132, 47-70.

Mirsky, A. F., Pascualvaca, D. M., Duncan, C. C., & French, L. M. (1999). A model of attention and its relation to ADHD. Mental Retardation and Developmental Disabilities Resaerch Reviews, 5, 169-176.

Posner, M. I., & Raichle, M. E. (1994). Images of mind. New York: Scientific American Books.

Posner, M.I. & Rothbart, M.K. (in press), Educating the Human Brain. Washington, D.C.:APA Books

Romski, M. A. (1989). Two decades of language research with great apes. American Speech-Language-Hearing Association, 31, 81-83.

Romski, M. A., & Sevcik, R. A. (1996). Breaking the Speech Barrier: Language Development through Augmented Means. Baltimore, MD: Paul H. Brookes Publishing.

Rueda, M.R., Rothbart, M.K.. & Saccamanno, L. & Posner, M.I. (2005) Training, maturation and genetic influences on the development of executive attention. Proceedings of the U.S National Academy of Sciences, 102, 14931-14936.

Rumbaugh, D. M., Richardson, W. K., Washburn, D. A., Savage-Rumbaugh, E. S., & Hopkins, W. D. (1989). Rhesus monkeys (Macaca mulatta), video tasks, and implications for stimulus-response spatial contiguity. Journal of Comparative Psychology, 103, 32-38.

Rumbaugh, D. M., & Washburn, D. A. (2003). The Intelligence of Apes and other Rational Beings. New Haven, CT: Yale University Press.

Savage-Rumbaugh, E. S. (1986). Ape language: From conditioned response to symbol. New York: Columbia University Press.

Stankov, L. (1988). Attentional resources and intelligence; A disappearing link. Personality and Individual Differences, 10, 957-968.

Washburn, D. A. (1994). Stroop-like effects for monkeys and humans: Processing speed or strength of association? Psychological Science, 5, 375-379.

Washburn, D. A. (2003). The games psychologists play (and the data they provide). Behavior Research Methods, Instruments, and Computers, 35, 185-193.

Washburn, D. A., & Rumbaugh, D. M. (1992). Investigations of rhesus monkey video-task performance: Evidence for enrichment. Contemporary Topics in Laboratory Animal Science, 31, 6-10.

Washburn, D. A., & Taglialatela, L. A. (2006). Attention as it is manifest across species. In T. Zentall & E. Wasserman (Eds.), Comparative Cognition: Experimental Explorations of Animal Intelligence, Oxford University Press.

About the Author

David A. Washburn is Professor of Psychology and Director of the Language Research Center at Georgia State University, from which he received his PhD in 1991. His research is broadly focused on the emergence of cognitive competence. More specifically, he and his collaborators investigate the significance of individual and group (including species) similarities and differences in attention, executive functions, and learning. This research enjoys current and recent support from the NIH, the U. S. Army Medical Corps and Materiel Command, the Federal Aviation Administration, and other agencies. Additional information about this research and his Individual Differences in Executive Attention (IDEA) laboratory can be found on his Georgia State University faculty page.