Target‐mask shape congruence impacts the type of metacontrast masking

Abstract

Visual metacontrast masking may depend on the time intervals between target and mask in two qualitatively different ways: in type-A masking the smaller the mask delay from target the stronger the masking while in type-B masking maximal masking effect is obtained with a larger temporal delay of the mask. Variability in the qualitative apperance of masking functions has been explained by variability in stimuli parameters and tasks. Recent research on metacontrast masking has surprisingly shown that both of these types of functions can be found with an identical range of stimulation parameters depending on individual differences between observers. Here we show that obtaining clear-cut type-A masking depends on whether target and mask shapes are congruent or incongruent and whether observers use the cues available due to the congruence factor. Conspicuously expressed type-A masking is selectively associated with incongruent target-mask pairings. In the latter conditions target identification level significantly drops with the shortest target-to-mask delays.

Retinotopy of visual masking and non-retinotopic perception during masking

“…These results collectively support our earlier findings and rule out eye movement as an explanation for elimination of masking effect under predictable group motion condition. As mentioned, there have been reports of individual differences in masking functions; for example, for the same stimulus parameters, some subjects exhibit Type-A, whereas others have Type-B masking functions (Albrecht et al, 2010;Maksimov et al, 2011). Whereas much of this difference can be explained by different criterion contents used by subjects, there remains a possibility of inherent differences between subjects.…”

“…In other words, the metacontrast masking function appears to shift from type-B to type-A. The expression of type-A versus type-B metacontrast functions has been attributed to differences in stimulus parameters, criterion contents, or individual differences (Breitmeyer & Öğmen, 2006;Duangudom, Francis, & Herzog, 2007;Francis & Cho, 2008;Albrecht, Klapotke, & Matler, 2010;Maksimov, Murd, & Bachmann, 2011). In our study, the same subjects were used in the two conditions and the inspection of individual subject data showed that all subjects' metacontrast functions consistently showed increased masking at short SOAs in the Ternus-Pikler condition compared to the static control condition.…”

Single 5HTR2A-1438 A/G nucleotide polymorphism affects performance in a metacontrast masking task: Implications for vulnerability testing and neuromodulation of pyramidal cells

“…In one of our earlier papers using this paradigm we showed that there is indeed interaction between genetic variability exemplified in BDNF Val66Met, NRG1/rs6994992, and 5-HTTLPR polymorphisms on the one hand and certain behavioral effects of metacontrast on the other hand [18]. In the present study we used metacontrast data from that earlier experiment where stimuli and procedure were the same as in [14][15][16] and carried out new genotyping for 5HTR2A-1438A/G (rs6311).…”

“…Metacontrast masking functions can be either monotonically increasing (type-A functions) or nonmonotonic (type-B functions) [10,11]. Both the qualitative and quantitative expression of masking often depends also on the congruency between the target and mask shapes [14][15][16][17]. For example, in the trials with congruent target/mask shape when the target is square-shaped then mask is also square-shaped, but an incongruent mask for the square-shaped target represents a diamond shape.…”

“…In recent years a standard type of metacontrast paradigm has been developed [14][15][16] (see Section 2). We capitalize exactly on this paradigm to be compatible with other recent research and to bear in mind the development of a possible behavioral, metacontrast based test of genotype related vulnerability ( Fig.…”