Guy C. Van Orden

A ROWS is a ROSE: Spelling, sound, and reading

Skilled readers generally are assumed to make little or no use of words’ phonological features in visual word identification. Contrary to this assumption, college students’ performance in the present reading experiments showed large effects of stimulus word phonology. In Experiments 1 and 2, these subjects produced larger false positive error rates in a semantic categorization task when they responded to stimulus foils that were homophonic to category exemplars (e.g., ROWS for the category A FLOWER) than when they responded to spelling control foils. Additionally, in Experiment 2, this homophony effect was found under brief-exposure pattern-masking conditions, a result consistent with the possibility that phonology is an early source of constraint in word identification. Subjects did, however, correctly reject most homophone foils in Experiments 1 and 2. Experiment 3 investigated the source of this ability. The results of Experiment 3 suggest that subjects detected homophone impostors, such as ROWS, by verifying target foil spellings against their knowledge of the correct spellings of category exemplars, such as ROSE.

Self-Organization of Cognitive Performance

Background noise is the irregular variation across repeated measurements of human performance. Background noise remains after task and treatment effects are minimized. Background noise refers to intrinsic sources of variability, the intrinsic dynamics of mind and body, and the internal workings of a living being. Two experiments demonstrate 1/f scaling (pink noise) in simple reaction times and speeded word naming times, which round out a catalog of laboratory task demonstrations that background noise is pink noise. Ubiquitous pink noise suggests processes of mind and body that change each others dynamics. Such interaction-dominant dynamics are found in systems that self-organize their behavior. Self-organization provides an unconventional perspective on cognition, but this perspective closely parallels a contemporary interdisciplinary view of living systems.

Interdependence of form and function in cognitive systems explains perception of printed words.

Perception is described within a complex systems framework that includes several constructs: resonance, attractors, subsymbols, and design principles. This framework was anticipated in J. J. Gibsons ecological approach (M. T. Turvey & C. Carello, 1981), but it is extended to cognitive phenomena by assuming experiential realism instead of ecological realism. The framework is applied in this article to explain phonologic mediation in reading and a complex array of published naming and lexical decision data. The full account requires only two design principles: covariant learning and self-consistency. Nonetheless, it organizes and explains a vast empirical literature on printed word perception.

Scaling laws in cognitive sciences

Scaling laws are ubiquitous in nature, and they pervade neural, behavioral and linguistic activities. A scaling law suggests the existence of processes or patterns that are repeated across scales of analysis. Although the variables that express a scaling law can vary from one type of activity to the next, the recurrence of scaling laws across so many different systems has prompted a search for unifying principles. In biological systems, scaling laws can reflect adaptive processes of various types and are often linked to complex systems poised near critical points. The same is true for perception, memory, language and other cognitive phenomena. Findings of scaling laws in cognitive science are indicative of scaling invariance in cognitive mechanisms and multiplicative interactions among interdependent components of cognition.

Strategic control of processing in word recognition.

Strategic control of word recognition in a lexical decision task was examined by manipulating the similarity of nonword foils to real words (nonword lexicality). Overall correct reaction times to words and the advantage of high- over low-frequency words were greater when nonword foils were more wordlike. This was true for both illegal (BTESE) versus legal (DEEST) nonword foils and legal nonword versus pseudohomophone (BEEST) foils. The same pattern of results was replicated in a 2nd experiment in which the word targets were always irregular (e.g., HAVE). A 3rd experiment demonstrated a large frequency blocking effect for low-frequency words, given pseudohomophone foils. The results are applied to pathway selection and random-walk frame-works. For both framework, canonical models are developed, which characterize qualitative predictions of broad classes of models within that framework. We argue for a pluralistic approach to theory development that moves from lower to higher order isomorphisms between data and theory.

Human Cognition and 1/f Scaling

Ubiquitous 1/f scaling in human cognition and physiology suggests a mind-body interaction that contradicts commonly held assumptions. The intrinsic dynamics of psychological phenomena are interaction dominant (rather than component dominant), and the origin of purposive behavior lies with a general principle of self-organization (rather than a special neurocognitive mechanism). E.-J. Wagenmakers, S. Farrell, and R. Ratcliff (2005) raised concerns about the kinds of data and analyses that support generic 1/f scaling. This reply is a defense that furthermore questions the model that Wagenmakers and colleagues endorse and their strategy for addressing complexity.

The Emergent Coordination of Cognitive Function.

1/f scaling has been observed throughout human physiology and behavior, but its origins and meaning remain a matter of debate. Some argue that it is a byproduct of ongoing processes in the brain or body and therefore of limited relevance to psychological theory. Others argue that 1/f scaling reflects a fundamental aspect of all physiological and cognitive functions, namely, that they emerge in the balance of independent versus interdependent component activities. In 4 experiments, series of key-press responses were used to test between these 2 alternative explanations. The critical design feature was to take 2 measures of each key-press response: reaction time and key-contact duration. These measures resulted in 2 parallel series of intrinsic fluctuations for each series of key-press responses. Intrinsic fluctuations exhibited 1/f scaling in both reaction times and key-contact durations, yet the 2 measures were uncorrelated with each other and separately perturbable. These and other findings indicate that 1/f scaling is too pervasive to be idiosyncratic and of limited relevance. It is instead argued that 1/f scaling reflects the coordinative, metastable basis of cognitive function.

What do double dissociations prove

Brain damage may doubly dissociate cognitive modules, but the practice of revealing dissociations is predicated on modularity being true (T. Shallice, 1988). This article questions the utility of assuming modularity, as it examines a paradigmatic double dissociation of reading modules. Reading modules illustrate two general problems. First, modularity fails to converge on a fixed set of exclusionary criteria that define pure cases. As a consequence, competing modular theories force perennial quests for purer cases, which simply perpetuates growth in the list of exclusionary criteria. The first problem leads, in part, to the second problem. Modularity fails to converge on a fixed set of pure cases. The second failure perpetuates unending fractionation into more modules.

Dispersion of Response Times Reveals Cognitive Dynamics

Trial-to-trial variation in word-pronunciation times exhibits 1/f scaling. One explanation is that human performances are consequent on multiplicative interactions among interdependent processes-interaction dominant dynamics. This article describes simulated distributions of pronunciation times in a further test for multiplicative interactions and interdependence. Individual participant distributions of approximately 1,100 word-pronunciation times were successfully mimicked for each participant in combinations of lognormal and power-law behavior. Successful hazard function simulations generalized these results to establish interaction dominant dynamics, in contrast with component dominant dynamics, as a likely mechanism for cognitive activity.

The Pervasiveness of 1/f Scaling in Speech Reflects the Metastable Basis of Cognition.

Human neural and behavioral activities have been reported to exhibit fractal dynamics known as 1/f noise, which is more aptly named 1/f scaling. Some argue that 1/f scaling is a general and pervasive property of the dynamical substrate from which cognitive functions are formed. Others argue that it is an idiosyncratic property of domain-specific processes. An experiment was conducted to investigate whether 1/f scaling pervades the intrinsic fluctuations of a spoken word. Ten participants each repeated the word bucket over 1,000 times, and fluctuations in acoustic measurements across repetitions generally followed the 1/f scaling relation, including numerous parallel yet distinct series of 1/f fluctuations. On the basis of work showing that 1/f scaling is a universal earmark of metastability, it is proposed that the observed pervasiveness of 1/f fluctuations in speech reflects the fact that cognitive functions are formed as metastable patterns of activity in brain, body, and environment.