Stroop Interference Based on the Synaesthetic Qualities of Auditory Pitch

Abstract

The equivalence of perceptual experience across the sensory modalities, most vividly observed in synaesthetes, is rarely discussed in contemporary cognitive psychology. It is suggested, however, that the concepts and paradigms of human information processing are ideally suited to test, for example, the fundamental assumption that the synaesthetic qualities of a stimulus are rapidly and automatically encoded. In a preliminary experiment subjects were asked to rate each of four auditory tones on a series of 7-point scales defined by pairs of antonyms. The results confirmed that a pure auditory tone has a range of qualities, determined by its pitch, that are shared by stimuli in other modalities. The main experiment used a paradigm based on the Stoop interference effect. Here the 50 Hz and 5500 Hz tones served as incidental stimuli and the subjects were required to respond as quickly as possible by pressing one of two keys depending on which one of four possible words appeared in the centre of the screen. Subjects were found to respond more slowly when the qualities of the tone were incongruent with the synaesthetic qualities represented by the test word. The results confirm that synaesthetic qualities of pitch are rapidly and automatically encoded and that the products of this encoding automatically interact with the mechanisms responsible for identifying word meaning and/or with the post-identification decision processes.

Selective attention to Stroop dimensions: Effects of baseline discriminability, response mode, and practice

“…We measure Stroop congruity both in filtering and at baseline,' which is defined as a difference in classification reaction time (RT) between trials in which the color and the word correspond (i.e., congruent trials) and trials in which the color and the word conflict (i.e., incongruent trials). Congruity measures have frequently substituted for Stroop's original measure (see, e.g., Nealis, 1973;Schulz, 1979;Sichel & Chandler, 1969;Simon & Berbaum, 1990;Simon & Sudalaimuthu, 1979; G. J. W. Smith, 1970) and have been used in tests of many other dimensions whose values have a correspondence quality (e.g., Clark & Brownell, 1976;Melara, 1989;Redding & Tharp, 1981;Walker & S. Smith, 1984).…”

Cross-sensory correspondences and cross talk between dimensions of connotative meaning: Visual angularity is hard, high-pitched, and bright

“…As part of their commitment to the notion that elementary stimulus features have connotative meanings, Karwoski et al (1942) proposed an early precursor of more recent claims that cross-sensory correspondences can reflect the semantic coding of such features (e.g., Martino & Marks, 1999;Walker & Smith, 1984). Karwoski et al suggested that cross-sensory correspondences arise from extensive crossactivation between corresponding places on dimensions of connotative meaning that are aligned with each other.…”

“…For example, people classifying simple visual stimuli according to their brightness or angularity respond more easily when a concurrent auditory tone has corresponding pitch (i.e., high for bright and angular, low for dark and curved) than when it does not have corresponding pitch (i.e., low for bright and angular, high for dark and curved) (Marks, 1987). Because pitch is incidental to the requirements of the task in this situation, registration of its cross-sensory connotations of brightness and angularity is thought to be automatic (see, e.g., Walker & Smith, 1984).…”

“…For example, when people draw the visual imagery they experience when listening to short musical selections, they draw lines and forms that tend to be thinner, brighter, smaller, and more angular (sharper) the higher in pitch and/or faster in tempo the music is (Karwoski et al, 1942). And when presented with simple sounds, they judge higher-pitched sounds to be brighter, 2 faster, harder, higher in space, lighter in weight, sharper, and smaller than lower-pitched sounds (Collier & Hubbard, 2001;Eitan & Timmers, 2010;Hubbard, 1996;Marks, 1974Marks, , 1975Marks, , 1978Mondloch & Maurer, 2004;Perrott, Musicant, & Schwethelm, 1980;Walker & Smith, 1984).…”

“…3 illustrates the processes and types of representation hypothesized to be involved in a version of the speeded classification task, devised by Walker and Smith (1984, 1985, 1986, for which only a semantic correspondence of the kind proposed by Karwoski et al (1942) can induce a congruity effect. Taking brightness classification for the purpose of illustration, individual test words are classified according to whether they refer to something bright or to something dark.…”