Taxonic Structure of Infant Reactivity: Evidence From a Taxometric Perspective

Abstract

Previously, we proposed a theoretical framework that classified infants into qualitative categories of reactivity, rather than on a continuous dimension. The present research used an objective statistical procedure (maximum covariance analysis, or MAXCOV) to determine if a qualitative latent structure, consistent with our theoretical conjectures, would be found to underlie quantitative indices of reactivity to stimuli in a sample of 599 four-month-old infants. Results of the MAXCOV analysis showed clear evidence of a latent discontinuity underlying the behavioral measures of infant reactivity. The base rate of the latent class (or taxon) was estimated at 10%. Infants within the putative high-reactivity taxon, compared with infants not in the taxon, were elevated on measures of behavioral inhibition at 4.5 years. These results provide objective empirical support for a central tenet in our theoretical model by supporting the taxonicity of infant reactivity.

Colic and fussing in infancy, and sensory processing at 3 to 8 years of age

“…Sensory contributions to emotional reactivity in this colic sample are further supported by the moderate and significant inverse correlations found between hours of fussing and the Sensory Profile subtests Tactile, Auditory, Visual Processing, and Emotional Reactivity. Similar to sensory-processing theory, some authors have suggested that temperamental differences such as low sensory thresholds, reduced soothability, and increased motor activity in response to stimuli may account for emotional reactivity (Canivet et al, 2000;Carey, 1972;Rothbart, Ziaie, & O'Boyle, 1992;Woodward, Lezenweger, Kagan, Snidman, & Arcus, 2000). Many items on the Emotional Reactivity subtest of the Sensory Profile are similar to temperament questionnaires such as "cries easily, displays excessive emotional outbursts, has temper tantrums, poor frustration tolerance, and difficulty tolerating changes in routines."…”

“Social Anxiety Disorder Carved at its Joints”: Evidence for the taxonicity of social anxiety disorder

“…For example, there is evidence of a high-reactivity taxon in infant temperament (Woodward et al, 2000) and indications of a social anxiety disorder phenotype for high reactivity/behavioral inhibition in infants (see Kagan, 2001;Schwartz et al, 1999;.…”

“…For example, consistent with a taxonic (i.e., categorical) conceptualization of social anxiety disorder, behavioral inhibition (i.e., a temperament characterized by early manifested traits which endure over time; Kagan, 2001) and high infant reactivity (i.e., a proposed developmental precursor to behavioral inhibition; see Woodward, Lenzenweger, Kagan, Snidman, & Arcus, 2000), have been suggested as discrete causal factors in the etiology of this disorder (Kagan, 2001). To illustrate, a high-reactivity taxon has been identified in 4-month-old infants wherein elevated behavioral inhibition has been demonstrated in taxon class members at 4-year follow-up (Woodward et al, 2000).…”

“…For example, consistent with a taxonic (i.e., categorical) conceptualization of social anxiety disorder, behavioral inhibition (i.e., a temperament characterized by early manifested traits which endure over time; Kagan, 2001) and high infant reactivity (i.e., a proposed developmental precursor to behavioral inhibition; see Woodward, Lenzenweger, Kagan, Snidman, & Arcus, 2000), have been suggested as discrete causal factors in the etiology of this disorder (Kagan, 2001). To illustrate, a high-reactivity taxon has been identified in 4-month-old infants wherein elevated behavioral inhibition has been demonstrated in taxon class members at 4-year follow-up (Woodward et al, 2000). Nearly two-thirds of adolescents classified as behaviorally inhibited at 13 years of age have been shown to meet diagnostic criteria for social anxiety disorder at 11-year follow-up; in contrast, only one-fourth of same-age peers initially classified as uninhibited later met criteria for social anxiety disorder at 11-year follow-up (Schwartz, Snidman, & Kagan, 1999).…”

EEG asymmetry, power, and temperament in children

“…Analyses based on both a finite mixture model (Stern, Arcus, Kagan, Rubin, & Snidman, 1994) and maximum covariance analysis (Woodward, Lenzenweger, Kagan, Snidman, & Arcus, 2000) have shown that a categorical conception fits the 4-month data better than one that assumes a continuum of reactivity.…”