The impact of global and local processing on the perceived adjustment error in the Muller-Lyer illusion. A test of Day’s (1989) Conflicting Cues Theory.
Abstract
The nature of visual illusions is hotly debated in the scientific literature, in search of a theory to explain how perceptual distortions arise upon daily interactions with the world. The present study provides the first direct test of Day’s (1989) Conflicting Cues theory to account for the Muller-Lyer illusion. Perceptual compromise was investigated, by measuring the impact of global and local processing on perceptions of size, as modulated by Navon stimuli. Following exposure to global, local or neutral cues, participants adjusted
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However this notion of regression towards the mean, has not withstood experimental manipulation of the fins-out Muller-Lyer figure (Day, 1989). Confusion theory on the other hand (Sekuler & Erlebacher, 1971), stipulates that the illusion is determined by the inter-tip distance between the arrowheads, where the larger distance of the fins-out arrangement and the smaller distance of the fins-in arrangement results in perceptual expansion and contraction, respectively .Like Assimilation theory, Confusion theory fails to accurately predict the size of the constant error for the experimental manipulation of the fins-out arrangement (Sekuler & Erlebacher, 1971). The inability of a single theory to account for all forms of the illusion has led some researchers to conceptualize Muller-Lyer as two distinct illusions. Nevertheless, echoing the common theme of perceptual averaging, Day (1989) proposed the Conflicting Cues theory to account for Muller-Lyer as a unitary phenomenon. Herein, the conflict between two cues for size, namely the actual line length and overall length of the figure, is resolved via a compromise between local and global processing in the brain. The present study investigates the relevance of perceptual compromise to the Muller-Lyer illusion.
The role of global and local processing has previously been investigated with the use of Navon stimuli (Navon, 1977). Herein, large letters are comprised of smaller letter elements. Indeed, studies
In another study, five experiments were conducted to determine if coloring a single Stroop element reduced automaticity or slowed the processing of a color. The results demonstrated that indeed it slowed processing of congruent and neutral stimuli more than it slows processing of incongruent stimuli (Monahan, 2001).
The Stroop (1935) effect is the inability to ignore a color word when the task is to report the ink color of that word (i.e., to say "green" to the word RED in green ink). The present study investigated whether object-based processing contributes to the Stroop effect. According to this view, observers are unable to ignore irrelevant features of an attended object (Kahneman & Henik, 1981). In three experiments, participants had to name the color of one of two superimposed rectangles and to ignore words that appeared in the relevant object, in the irrelevant object, or in the background. The words were congruent,
(1) The first question is dealing with the causal or functional role of phenomenal qualities: Under the assumption that seeing is based on cortical information-processing, the question arises, whether the phenomenal qualities of visual perceptions have a function with regard to this processing, in the sense that the intentional content of visual perceptions depends not only on their intentional, but also on their phenomenal qualities. Is it true, as among other authors Frank Jackson and Steven Pinker claim, that phenomenal qualities are only epiphenomena, not having any function for information-processing? (1)
This study examined visual perception and the rates at which global and local features are reacted to with an aim of replicating and validating a previous experiment conducted by Navon (1977) to see if global processing was faster than local processing. There was 222 University of Newcastle students participating in the experiment, partaking in two phases, one centred round global processing, the other around local processing, where there reaction times were recorded using a computer program and imputed into a data worksheet. Results indicated that, as predicted, global processing occurred at a faster rate than local processing. It was concluded that global features were
The current experiment is being run to investigate whether the global superiority effect is affected by the type of symbol, using a divided attention task. In previous studies Navon (1977), cited in Ness et al. (2014), used global letters made up of local letters to test how we process visual information. However, Yovel’s (2001), cited in Ness et al. (2014), divided attention task had two parts. Firstly, to see whether participants would react more quickly to global than local letters; and secondly, that there would be no difference to global and local target letters if the local letters were larger. In the current experiment the stimuli were global shapes and letters made up of local shapes and letters. They were tested to see the impact on processing and response times. The key features of the design was a 2x2 repeated measures design, and the participants performed on all four conditions which were two (IV’S) each with two levels.
Powell (1986) conducted a study in which individuals viewed a photo or slide. Individuals were required to scan images and decide on an image for the entire display (Powell, 1986). Objects were pointed to, and subjects were asked to identify its location (Powell, 1986). The subject was asked to close his or her eyes and were shown another image. The subjects were to decide if the object was in the correct position (Powell, 1986). The subjects would hear one of the objects and was required to focus on the object while keeping the entire image in his or her mind (Powell, 1986). When the next object was identified, the subjects were to move from the first object to the second watching a black dot moving in a straight line (Powell, 1986).
To develop an understanding of the metric system and use it to measure common objects. To also learn about how to report uncertainty in your measurements.
The aim of this study was to further investigate whether the interpretation of an ambiguous stimulus is influenced by immediate past experience, and, therefore, by the establishment of a perceptual set. It is based on an experiment conducted by Bugelski and Alampay (1961).
Patients tend to correctly identify shape, color, and motion of inputs. In a forced choice experiment, where the subject is asked to identify certain features of a visual cue, the subject will perform much better than chance even though they feel as if they are randomly guessing (2).
Among those in support of the claim that change blindness and inattentional blindness reveal a grand illusion of visual perception, Cohen identifies three interpretations of the illusory beliefs in which the grand illusion is understood: world richness, representational richness, and representational reality. Although Cohen forms arguments against each interpretation of illusory beliefs, as stated earlier, this paper will focus on the idea of the grand illusion in regards to the illusory belief of representational
1. The authors decided to do a replication of a study performed by of Ramachandran & Hubbard (2001) and Hubbard (2005). From this study researchers looked at individuals who had synaesthetes and how they interpreted shapes, numbers and colors. Results from their study showed that individuals who had synaesthetes performed better by interpreting certain pictures by using more of the ‘pop-out’ effect rather than using the serial search effect. It also “assumed that color and shapes are processed independently, which does not hold true for people who have synathecia, giving that some amount of grapheme processing must be required for the color to be included”(Ramachandran & Hubbard 2001b, 2003b). Due to these findings researchers decided to “correct”
While Klein (2000)'s research did aim to recreate this phenomenon clearly, the current study differentiated its self by introducing the letters L and T as cues to which provided no information about the location of the target as the presentation. As presentation of a single cue meant it was four times more likely for a cue and a target to appear on the same side. The purpose of this variation was that a majority of previous studies had presented the facilitation effect and the IOR effect in a scenario where the cues were equally as
The article by Avital-Cohen and Tsal (2016) discussed the flanker task experiment, which asserted that distractor interference happens unconsciously as a result of focused attention toward the target. The results from the original flanker task indicated that participants had slower responses for incongruent trials, since the distractors are inconsistent with the target and would require a different response (Avital-Cohen & Tsal, 2016). However, Avital-Cohen and Tsal (2016) questioned the findings from the flanker task experiment. They decided to challenge the idea that only the target stimuli receives top-down processing, and not the distractors (Avital-Cohen & Tsal, 2016). The first experiment aimed to test whether the distractor interference is purely bottom-up processing as claimed in the flanker task. The experiment manipulated participants’ expectations of the target using the context effect - a type of top-down processing - by changing the distractors to be either letters or digits (Psych 240 lecture, 9/21/16). Then, the researchers conducted a second experiment and eliminated the ambiguity of distractors. They wanted to test whether the result from experiment 1 was caused by an overall bias or the ambiguous distractors. In experiment 2, the researchers predicted that they would obtain similar results to the first experiment only if the results were due to an overall bias effect (Avital-Cohen & Tsal, 2016). This study allows us to deepen our understanding of available
Buckingham, Milne, Byrne and Goodale’s article, published in the eminent journal ‘Psychological Science’, focuses on the ability of echolocation and the credibility of it obtaining a ‘sensory substitution’ status. What comes with such a status, includes the testing of falling into perceptual ‘traps’. In this research, the authors are interested in whether echolocation, and its users, commit the ‘Size-Weight Illusion’. This is a visual perception trap whereby the perception of an object’s characteristics (size) can be influenced by its appearance (Charpentier, 1891). This notion is aptly condensed into an informative title “The Size-Weight Illusion induced through Human Echolocation” (p. 237).
We are replicating J.R. Stroop’s original experiment The Stroop Effect (Stroop, 1935). The aim of the study was to understand how automatic processing interferes with attempts to attend to sensory information. The independent variable of our experiment was the three conditions, the congruent words, the incongruent words, and the colored squares, and the dependent variable was the time that it took participants to state the ink color of the list of words in each condition. We used repeated measures for the experiment in order to avoid influence of extraneous variables. The participants were 16-17 years of age from Garland High School. The participants will be timed on how long it takes them to say the color of the squares and the color of the words. The research was conducted in the Math Studies class. The participants were aged 16-17 and were students at Garland High School. The results showed that participants took the most time with the incongruent words.