a theory of intelligence as processing implications for

Psychology, Public Policy, and Law Copyright 2000 by the American Psychological Association, Inc. 2000, Vol. 6, No. 1, 168-179 1076-8971/00/$5.00 DOI: 10.1037//1076-8971.6.1.168

A THEORY OF INTELLIGENCE AS PROCESSING Implications for Society

Joseph F. Fagan III Case Western Reserve University

Defining intelligence as processing allows one to predict intelligence from infancy, discover causes of mental retardation, test the intelligence of people with disabilities, develop culture-fair tests of intelligence, and demonstrate that groups that differ in IQ do not necessarily differ in intelligence. An early estimate of intellectual disability allows a child to qualify quickly for remedial programs. Economic and emotional benefits would ensue from discovering and eliminating the causes of a small percentage of cases of mental retardation. The measurement of intelligence as processing reveals intellectual strengths that may otherwise be masked by physical or emotional disability or by cultural circumstances. Cultures may differ in the types of knowledge their members have but not in how well they process. Cultures may account for racial differences in IQ.

The purpose of this article is to consider the implications for society of defining intelligence as processing. My belief is that controversy surrounding the term intelligence has arisen and continues because intelligence has historically been defined as how much one knows rather than as how well one processes. IQ scores, by convention, are based on how much one knows relative to one's age peers. My theoretical position (Fagan, 1992; Fagan & Haiken-Vasen, 1997) is that intelligence is processing and that processing can be measured by performance on certain elementary cognitive tasks. An IQ score, on the other hand, depends not only on processing ability but on what one has been taught. To state my theory briefly, as information is processed, the mind changes. That change is called knowledge. Knowledge is a state of mind. How well we process depends on our genetic plan and on the good or ill that the world has physically inflicted on our brain. Culture provides us with information. What we know depends on how well we process and on what our culture teaches us.

Defining intelligence as processing frees intelligence from its historic definition as the score (IQ) on an intelligence test and makes intelligence an integral and legitimate object of study across all areas of psychology and disciplines related to psychology. Defining intelligence as processing has the additional practical advantage of providing a common metric with which to study intelligence across species. Most important for our present purposes, defining intelligence as processing clarifies theoretical issues in the field of intelligence and, in so doing, may change lives.

Preparation of this article was supported in part by Mental Retardation Training Grant HD 07176 from the National Institute on Child Health and Human Development. I am indebted to Nina Engelhardt for gathering the data listed in Table 1.

Correspondence concerning this article should be addressed to Joseph F. Fagan III, Department of Psychology, Case Western Reserve University, Cleveland, Ohio 44106. Electronic mail may be sent to [email protected].

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INTELLIGENCE AS PROCESSING 169

Overview

In what follows, I show how the assumption that intelligence is processing allows us to predict childhood IQ scores from infancy and how intelligence defined as processing leads to the conclusion that Whites and Blacks, while different in average IQ, are equally intelligent (Jenson, 1985). I point out some practical implications for the definition of mental retardation and the search for its causes that flow from the fact that intelligence is continuous over age. The measurement of intelligence in special populations also is considered. I note how the fact that Blacks and Whites are equally adept at processing provokes a search for specific cultural causes of average IQ differences between groups (Jenson, 1985). I point out that defining intelligence as processing can make the hope for culture-fair tests of intellectual functioning a reality. Finally, I mention some of the additional policy implications that proceed from defining intelligence as processing.

Predicting Later IQ From Processing During Infancy

If intelligence is defined as processing and if processing can be measured during infancy, than we should be able to predict how much a child will know at a later age. A paradigm that I have found useful for the measurement of processing is based on the fact that from birth, humans attend more to novel than to previously exposed stimuli (Fagan, 1970, 1990). By definition, if a new target can be differentiated from a previously exposed target, information processing has taken place. Is the nature of intelligence continuous with age? Does a child who was a good processor as an infant know more than an age peer who was a poor processor during infancy? Yes. Measures of information processing taken during infancy predict IQ scores obtained during childhood (see reviews by Fagan & Detterman, 1992, and McCall & Carriger, 1993).

The fact that simple measures of information processing such as selective attention to novelty can predict IQ scores has practical implications for our definition of mental retardation and for the search for the causes of mental retardation. A key priority of the National Institute of Child Health and Human Development (NICHD) has been the development of methods to identify infants at risk of becoming mentally retarded.

Supported, in part, by various grants from NICHD, a screening device has been developed that has proven to be valid in predicting later mental retardation from infancy (e.g., Fagan & Shepherd, 1992). The screening device, known as the Fagan Test of Infant Intelligence, is based on the infant' s attention to novelty. The rationale behind the Fagan test is based on the definition of intelligence as processing. If intelligence is processing, than mental retardation is a deficit in processing. If a person begins life as a poor processor, that person would be expected to know less (i.e., have a low IQ score) later in life. A technical summary of the Fagan test along with data confirming the sensitivity of the test for the identification of mental retardation later in life is given in Fagan and Detterman (1992).

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Finding the Causes of Mental Retardation

A number of implications for society arise from the fact that it is now possible to predict which infants are likely to be intellectually delayed later in life. Perhaps the most salient implication is that the lead time for the prospective study of the causes of mental retardation has been greatly reduced. With conventional IQ tests, 3 to 6 years must typically pass before retardation in the 50-70 IQ range can be diagnosed--an IQ range encompassing almost 90% of retarded children. The development of an intelligence test for infants that is based on the definition of intelligence as processing has meant that the lead time on prospective studies of the causes of mild mental retardation can be cut to less than a year. Investigators have been quick to take advantage of a test of intelligence that is based on processing, to search for the causes of mental retardation (Fagan, 1992). The Fagan test is now in use in over 200 research centers around the world. Some are using the Fagan test to study the effect that exposure to various chemical agents, such as PCBs (polychlorinated biphenyls), alcohol, cocaine, lead, and mercury have on intellectual development. Others are concerned with the role of nutrition, iron supplements, and fatty acids on early intelligence. The intellectual sequelae of thyroid deficiency, maternal HIV infection, intraventricular hemorrhage, bron- chopulmonary dysplasia, failure to thrive, intrauterine growth retardation, very preterm birth, genetic anomalies, various neurological abnormalities, and the effects of early surgical procedures also are being assessed.

I hope that researchers using tests of processing may discover the etiology of certain cases of mental retardation (e.g., by identifying teratogens). Capitalizing on such identification, legislators will, presumably, institute programs to prevent specific causes of retardation. Obviously, any legislation to prevent identified causes of mental retardation must accommodate conflicting social and economic interests. Even a very limited success, however, in discovering the causes of mental retardation and eliminating those causes would be of enormous social benefit. To put that benefit into perspective, consider the fact that we currently invest about $14 million a year to screen infants for phenylketonuria (PKU), a highly worthwhile endeavor, which no one would question. However, finding and eliminating the causes of just 1% of mild-to-moderate retardation would save more children from intellectual deficit each year than are now saved by screening and treatment for PKU. Economically, as Baumeister, Bacharach, and Baumeister (1997) have pointed out, the savings to society of preventing even a small percentage of the cases of mental retardation each year can be measured in billions of dollars. Added to the monetary savings is the personal value to children and parents, a value that cannot be measured in dollars but is a great sum in emotional currency. In effect, the cost to society of supporting research aimed at discovering the causes of poor processing is trivial compared with the benefits to be gained.

Measuring Intell igence in Special Populations

The assumption that intelligence is processing also allows us to estimate the intelligence of individuals who cannot be given standard IQ or developmental tests for reasons unrelated to intellectual functioning per se. Difficulties in test compliance may be due, among other things, to anxiety, to culturally imposed


limits on language comprehension, or to motor disabilities. Thus, extraneous influences, which may vary with the requirements of IQ tests, may limit the conclusions one can come to as to a person with a disability's intellectual functioning. Such limitations can be overcome by defining intelligence as processing. The measurement of processing by means of selective attention to novelty, for example, does not require a verbal response, requires only the ability to make eye movements, makes no demands that would provoke anxiety, has no instructions to be followed, and allows the tester observing the person's eye movements to verify that compliance has occurred. Under such test conditions, I have found that special populations, such as autistic children, adults with acquired neurological impairment, or depressed or demented older people--although not as proficient in selective attention as normal controls--are, nonetheless, able to devote selective attention to novelty, thus yielding measurable individual differences in processing (Fagan & Haiken-Vasen, 1997). Findings have been similar for females diagnosed with Rett syndrome, a neurological disorder characterized by severe or profound retardation, lack of functional hand use, and an inability to follow instructions (von Tetzchner et al., 1996).

In some cases, the measurement of intelligence as processing has shown that intelligence is not impaired despite otherwise debilitating circumstances. Drotar et al. (1997), for example, have shown that HIV-infected infants, despite lower levels of sensorimotor development, are capable of age-appropriate visual information processing. Droter.~ Mortimer, Shepherd, and Fagan (1989), using tests of selective attention to novelty, have demonstrated normal intellectual functioning on the part of an infant with quadriplegia, despite the infant's severe physical disability and a life spent in the hospital. The child was eventually placed in a nursing home for physically impaired children who are intellectually intact.

Professionals who treat people from special populations constantly seek more valid and efficient tests of intelligence, for screening, to monitor the course of intellectual decline, and to evaluate treatment. The number of people who can profit from tests of intelligence based on processing is quite sizable. In addition to the populations already mentioned are people who complain of age-associated memory impairment, patients with various neurological disorders, individuals with mental disorders, people with speech, hearing, or language impairment, those with developmental disorders, and those who evidence cultural bias (a loose term covering the economically disadvantaged and cultural minorities from different language backgrounds). Table 1 lists the approximate number of people who might profit from tests of intelligence that are based on processing.

All of the 64 million people listed in Table 1 are accessible to health care professionals. The first 44 million listed are being seen on some regular basis. The remaining 20 million, listed under cultural bias, are about 7% of the U.S. population and are seen in public schools, community health agencies, job- retraining programs, and major urban hospitals. The numbers listed in Table 1 are gross estimates on the basis of the size of the U.S. population and what data I could find on the prevalence of individuals in each category. The point of constructing Table 1 is not to be exact, but simply to indicate that the number of people in need of an alternative to conventional IQ tests of intelligence is sizable.

In brief, defining intelligence as processing allows the measurement of intelligence in individuals for whom the administration of IQ tests would be

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Table 1 Special Populations Who Cannot Comply With the Requirements of Standard IQ Testing

Population Number

Age-associated memory impairment Neurological disorders

Stroke Trauma Movement disorders Dementias Neuromuscular disorders

Mental disorders Schizophrenia Major depression Bipolar disorders

Language comprehension- production disorders

Developmental disorders Cultural bias

Total

20,000,000

2,000,000 1,000,000

500,000 4,000,000 2,000,000

2,500,000 2,500,000 2,000,000

2,500,000 5,000,000

20,000,000 64,000,000

inappropriate. The measurement of processing in special populations can provide baseline and outcome measures in assessing the effectiveness of therapies aimed at the remediation of certain disorders characterized by intellectual dysfunction (e.g., Alzheimer's disease). For particular individuals, the measurement of processing can also reveal an intellectual strength that might otherwise be masked by physical disability.

Racial Differences in IQ but Not in Intell igence

Let us now consider how the definition of intelligence as processing can aid in answering the question of what causes differences in IQ among groups of people. Theoretically, the answer depends on whether group differences in processing accompany group differences in IQ. I would assume that in the absence of processing differences among groups, differences in IQ are most likely due to cultural influences.

We are also aided in understanding group differences in IQ by noting those that must be due to culture. Schooling effects are a clear instance of group differences in IQ that must be due to the presence of differences in the culture's provision of information. A comprehensive review of the extent to which various factors associated with schooling have their effects on IQ is provided in Ceci (1991). I focus on studies of children who were born just before or just after an arbitrary cutoff date for school entry. The fact that one was born before or after an arbitrary date obviously has nothing to do with either one's genetic plan or with the physical effects of the environment on the brain (i.e., with factors that influence processing). But being born before or after a particular date may have a great deal to do with whether a child is in the fourth or the fifth grade by the age 10 and, consequently, with how much that child has been taught by the age of 10.

Cahan and Cohen (1989) conducted the archival study of the effects of cutoff


dates for school entry on intelligence test scores. They administered portions of 12 different standard IQ tests to over 11,000 fourth, fifth, and sixth graders attending the state-administered elementary schools in Jerusalem in 1987. The results were unambiguous. Schooling affected raw intelligence test scores on all 12 tests, including the Raven Progressive Matrices (Raven, Court, & Raven, 1975). I mention the Raven test because it is highly g loaded (Jensen, 1993a) and, by implication, has been thought not to be subject to cultural influence. Cahan and Cohen (1989) have concluded that schooling is the major reason that intelligence test scores increase with age.

As one might expect, schooling effects owing to cutoff dates have also been found for other tests of knowledge such as reading and mathematics (Morrison, Griffith, & Alberts, 1997). Schooling effects, however, have also been found for tasks that one would usually consider to be elementary cognitive tasks and unlikely to be subject to cultural influences. Cognitive tasks influenced by schooling include phonetic segmentation (Bentin, Hammer, & Cahan, 1991; Morrison, Smith, & Dow-Ehrensberger, 1995), short-term recall (Ferreira & Morrison, 1994; Varnhagen, Morrison, & Everall, 1994; Morrison et al., 1995), and mental arithmetic (Bisanz, Morrison, & Dunn, 1995). Tasks that appear to be tests of processing are subject to schooling effects. Hence, the definition of processing must be derived from a theoretical understanding of the task in question and not simply assumed on the basis of the superficial characteristics of the task. I return to the discussion of cultural influences on what appear to be elementary cognitive tasks as I discuss racial differences in IQ. For the moment, however, bear in mind that schooling effects provide a clear example of the influence of a cultural factor on what are conventionally designated as tests of intelligence, achievement, and basic cognitive functioning. Schooling effects must reflect the influence of the culture on what one knows. Thus, tasks affected by schooling must be, to some degree, culturally influenced.

Racial differences in IQ are a prime example of the application of the procedural guideline that I suggest for the determination of group differences in IQ. Differences in average IQ between Blacks and Whites on the order of about 1 standard deviation (about 15 IQ points) are well documented (Jensen, 1985) and are present as early as 3 years of age (Fagan & Monfie, 1988; Peoples, Fagan, & Drotar, 1995). I make no attempt here to trace the history of the arguments that have been made for the causes of racial differences in IQ. The interested reader may consult the historical discussions contained in Block and Dworkin (1976) or the references cited by Neisser et al. (1996). Suffice it to say that there are those who lean toward a genetic explanation and those who favor a cultural explanation of Black-White differences in IQ.

I accept the evidence for IQ differences between Blacks and Whites at face value. Theoretically, I ask if the presence of racial differences in IQ is accompanied by differences between Blacks and Whites on measures of the spontaneous processing of information. If so, the search for the causes of Black-White differences in IQ should be directed toward genetic or physical environmental factors. If not, the search should concentrate on cultural influences.

As I noted in my discussion of schooling effects on IQ, performance on some elementary cognitive tasks may be culturally influenced. Thus, one must be cautious in attributing racial differences in IQ to processing differences on the

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basis of any or all cognitive tasks. A case in point is the study reported by Jensen (1993b) of 585 White and 235 Black schoolchildren whose reaction times were measured on what appeared to be simple information-processing tasks. Jensen used four tasks, which varied in the time taken for successful solution. The easiest task was a simple reaction time task in which the time taken to lift one's finger from a home key on presentation of a signal from a single source was measured. A slightly more demanding task measured the same reaction times when the signal to respond came from any one of eight sources. In a more complex discrimination task, reaction time was measured when three signals (out of eight) were activated at once and the child had to decide which of the three was located at the greatest distance from the other two before reacting. The most demanding task was the measurement of reaction times over a series of mental arithmetic problems involving addition, subtraction, or multiplication of single-digit numbers.

Jensen's results (taken from the data given by Jensen, 1993b, in his Appen- dices A and B) indicated that mean reaction times for Blacks and Whites did not vary on the two simple tasks but did differ on the two more demanding tasks. As noted in the summary of schooling effects, age of school entry alters performance on tests of short-term memory and the speed of solution of mental arithmetic problems. Thus, the present theory suggests that the pattern of Jensen's (1993b) results may actually indicate the influence of a cultural factor on the performance differences of Blacks and Whites. The suggestion of the present theory as the reason for Jensen's results could easily be checked by using Jensen's four reaction time tasks in a study of children (of the same race and the same age) whose birthdates fall just before or just after an arbitrary cutoff date for school entry. If children of the same age who varied in schooling did not differ on Jensen's simple tasks but did differ on Jensen's more demanding tasks, it would mark the more demanding tasks (but not the simple tasks) as subject to cultural influences. The cultural factors affecting Black-White differences, of course, may not be the same as those influencing schooling effects.

In my own program, I have obtained IQ scores for 299 preschoolers at 3 years of age, who, as infants, were tested for attention to novelty. Attention to novelty is a processing task that does not vary for children of various school ages and is applicable from birth to senescence (Fagan & Haiken-Vasen, 1997). Of the 299, 35 children were Black, and 264 were White. All came from middle-class, suburban homes. Their parents, as a group, did not differ in level of education. In addition, I participated in a multisite, national study of 70 high-risk infants (34 White and 36 Black) from predominantly lower-class families, who were tested for visual attention to novelty as infants and for IQ on the Bayley Scales of Infant Development (Bayley, 1969) at 2 years of age (Fagan & Shepherd, 1992). Finally, as part of a dissertation by Haiken-Vasen (1995), we tested 96 schoolchildren (64 Black and 32 White), with a mean age of about 9 years (SD = 2.6), who were attending church-affiliated schools. The schoolchildren were tested for both visual attention to novelty and, on the Peabody Picture Vocabulary Test (Dunn & Dunn, 1981), for IQ. The specific procedures for testing the visual novelty preferences of older children and adults are given in Fagan and Haiken-Vasen (1997). With the exception of briefer study times, however, testing of attention to visual novelty


is the same for children as for infants, (i.e., there are no instructions as to what to attend to and processing is spontaneous).

Table 2 lists the average visual novelty preference scores and the average IQ scores for each of the three age groupings (2, 3, and 9 years). Weighted mean averages are listed for the 3-year-olds.

The data in Table 2 are quite clear. For each sample, White children were significantly different from Black children in IQ. In no case, however, do Whites and Blacks differ significantly in spontaneous processing.

On the basis of the assumptions that intelligence is processing and that IQ scores are a measure of knowledge, my interpretation of the results is that Black people are as intelligent as White people but that some Blacks do not know what some Whites know. My interpretation does not assume that one culture is superior or inferior to another but only that people from different cultures may differ in what they believe their children should be taught. One social policy implication of such an interpretation is that if we wish to understand the differences in the knowledge tapped on IQ tests that produces differences in performance between Blacks and Whites, we must discover the cultural practices that influence the teaching of particular kinds of knowledge.

According to my theory, the study of culture is the study of what interacts with processing to produce knowledge in a particular domain. Paradoxically, it is only by examining culture that the conventional definition of intelligence as IQ remains relevant. Is it important to understand culture as well as the processing determinant of IQ? Yes, for two reasons. First, IQ scores predict important life achievements, and the cultural factor is a significant source of variance in such prediction. Second, differences among groups in IQ may well involve the cultural factor. As noted, Black people and White people differ in IQ but do not appear to differ in spontaneous processing. The implication is that the source of Black- White differences in IQ is to be sought in the culture.

I suggest five guidelines for studying the influence of culture in the determi-

Table 2 Novelty Preference and IQ Scores for Black and White Children at 2, 3, and 9 Years of Age

Novelty preference IQ

Age 'White Black White Black

9

years M .61 .59 103.7 84.7 SD .07 .07 26.2 18.2 n 34 36 years M .60 .60 107.5 93.5 SD .07 .09 11.3 13.1 n 264 35 years M .58 .58 106.5 99.2 SD .05 .06 10.5 14.0 n 32 64

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nation of IQ. The first guideline is that the measurement of the culture should always be accompanied by the measurement of processing. Hart and Risley (1995), for example, have conducted a landmark longitudinal study of frequency of verbal stimulation and resulting vocabulary development of children from 1 to 3 years of age. The amount of exposure to language was positively correlated with vocabulary development and IQ scores of the children at 3 years. Unfortunately, because no measure of the children's processing of information was included in the design of the Hart and Risley (1995) investigation, there is no way to estimate the relative contributions of processing and the culture to the children's ultimate vocabulary knowledge or IQ. The lesson for future naturalistic or experimental observations of children's experience is to include measures of processing in one' s design, so that the differential effects of processing and cultural direction on knowledge can be assessed.

The second guideline is that the exploration of the influence of culture on knowledge should begin in the first few years of the child' s life. Empirically, we know from the Hart and Risley (1995) investigation that large differences in sheer exposure to important information take place during the first few years. Evidence also has been presented in the present article that demonstrates that differences in IQ between Blacks and Whites are present as early as 2 to 3 years of age. Thus, any manipulation of the culture factor with the goal of preventing a low IQ score should begin in the first few months and years of life.

The third guideline is fairly obvious. The samples from which we can learn the most in the search for those aspects of the culture that determine IQ are groups that differ in IQ but do not differ in spontaneous processing. Likely candidates are children of the same age that differ in schooling due to arbitrary cutoff dates for admission to school and children that differ in race.

The fourth guideline is to search for specific techniques that agents of the culture use to direct a child's attention to information. Saffran, Aslin, and Newport (1996), for example, have shown that infants at 8 months can segment words from ongoing speech solely on the basis of the relation between neighbor- ing speech sounds. But long before 8 months, mothers from various cultures speak in a more informative manner to their infants than they do to adults by empha- sizing particular sounds (Kuhl et al., 1997). Is it possible that individual differences in how mothers speak to their infants may influence the infant's subsequent segmentation of words from ongoing speech, which, in turn, may alter the size or composition of the child's vocabulary? Vocabulary knowledge, of course, plays a prominent role in most estimates of IQ.

The fifth guideline is to be eclectic in the search for cultural influences on knowledge. Theoretically, any variable that produces differences in knowledge among groups who do not differ in processing is a cultural variable. It does not matter whether the individuals being studied are humans or animals. It does not matter if the knowledge in question is complex problem solving or the avoidance of a shock. Any variance (aside from what is due to processing or error) that determines human cognition or animal learning may play a part in determining the cultural factor in IQ.

Although other examples of the search for the cultural sources of knowledge may be given, the point is that social policy is determined not so much by data but by the interpretation of data. The assumption that intelligence is processing leads


us to search the culture (rather than genetics) for the origins of racial differences in IQ.

Culture-Fair Tests of Intell igence Based on Processing

The definition of intelligence as processing may also accomplish a long- sought-after goal: tests of intelligence that are applicable to any culture. Fagan et al. (1991), for example, compared the performance of four culturally (and ra- cially) diverse groups on the Fagan Test of Infant Intelligence. The Fagan test is composed of 10 pairings of novel with previously seen items. The four groups did not differ in their mean attention to novelty, nor was there any evidence of test bias across the 10 items. In brief, tests of processing based on selective attention to novelty, at least with infants, have proved to be culture-fair. Thus, defining intelligence as processing may make culture-fair tests of intelligence a reality: a hope that cannot be fulfilled as long as intelligence is defined as knowledge.

Additional Implications

In conclusion, some additional implications of defining intelligence as processing may be mentioned. In the area of education, the definition of intelligence as processing can provide an early estimate of intellectual disability, thus allowing a child to qualify as soon as possible for available programs. Multiple criteria for inclusion in special programs are the norm. Hence, children who are good processors but have other disabilities or live in culturally disadvantaged circumstances would not be disenfranchised from special programs by their high processing scores. Rather, throughout preschooling and during the school years, placement in special education and the preparation of individual educational plans can be accomplished by a consideration of both processing strengths and weak- nesses in conjunction with measures of amount of knowledge. In medicine, tests of processing can serve as short-term outcome measures to assess the utility and the risk of medical procedures, particularly interventions undertaken with infants. In the area of disability entitlement, tests of processing can indicate intellectual ability as well as disability and might also provide a way to identify malingering. Finally, culture-fair intelligence tests that are based on processing may provide an objective means of selecting candidates for employment or for advanced education, thus fulfilling the spirit of affirmative action and equal opportunity programs.

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Received May 25, 1998 Revision received July 7, 1998

Accepted August 25, 1998 •

a theory of intelligence as processing implications for

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