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Michael T Turvey

Publications and source records attributed to Michael T Turvey.

7 recordsLinked to original sources
PubMed2006

Phonological assimilation and visual word recognition.

Are the visual word-processing tasks of naming and lexical decision sensitive to systematic phonological properties that may or may not be specified in the spelling? Two experiments with Hangul, the alphabetic orthography of Korea, were directed at the effects of the phonological process of assimilation whereby one articulation changes to conform to a neighboring articulation. Disyllabic words were responded to more quickly when (a) the final letter of the first syllable and the initial letter of the second syllable specified phonemes that satisfied rather than violated consonant assimilation, and (b) the vowel letters specified harmonious as opposed to disharmonious vowel phonemes. Discussion addressed the possible mediation of assimilation effects by consistency differences and theories that predict broad phonological influences on visual word recognition.

Humans↗
PubMed2006

Effects of visual environment on quiet standing by young and old adults.

The authors manipulated the circumstances in which individuals are typically embedded when standing upright by manipulating the intensity of light and the stationary structure of the environment. They expected that the manipulations would affect 12 older participants (aged 65-82 years) more than it would 12 younger participants (aged 22-24 years). Linear (e.g., total path length) and nonlinear (e.g., maximum line length of recurrent points in phase space) measures of the center of pressure time series confirmed that expectation. Moreover, for some measures, there was a suggestion that participants' visual contrast sensitivity (an index of neurophysiological age) was a more important contributing factor overall than was their chronological age. In the Discussion, the authors highlight the significance of interactive effects of environmental, organismic, and task constraints on quiet standing.

Adult↗
PubMed2005

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.

Brain↗
PubMed2005

Encoding and retrieval during bimanual rhythmic coordination.

In 2 experiments, bimanual 1:1 rhythmic coordination was performed concurrently with encoding or retrieval of word lists. Effects of divided attention (DA) on coordination were indexed by changes in mean relative phase and recurrence measures of shared activity between the 2 limbs. Effects of DA on memory were indexed by deficits in recall relative to baseline. For DA at both encoding and retrieval, the equilibrium values of relative phase were shifted and the degree of shared activity between left and right rhythmic motions was reduced. Recall was reduced, however, only for DA at encoding. The results corroborate and extend those obtained with more conventional secondary tasks (e.g., visual reaction time), suggesting attention dissimilarities between episodic encoding and retrieval.

Attention↗
PubMed2004

Symmetry and the devil.

F. Mechsner (2004) bases his argument for the primacy of perception on a simplified interpretation of phase transition findings. The authors show that attention to the details of phase transition analysis, as well as consideration of findings from steady-state experiments and the tools of symmetry theory, necessitate a theory of bimanual coordination that includes both perceptual and motor processes.

Humans↗
PubMed2003

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 other's 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.

Adult↗