Evaluating the Impact of Spatial Frequencies on the Perception of Gender

Kurczek, J. & Ohnesorge, C. (2010, August). Evaluating the Impact of Spatial Frequencies on the Perception of Gender. <i>Poster presentation at the Annual Summer Interdisciplinary Conference (ASIC)</i>, Bend, OR.<div> <div> <div> <div> <p><br></p><p>Face perception is fundamentally important for judging the characteristics of individuals, such <br> as identification of their gender, age, ethnicity or expression (Webster, Kaping, Mizokami, &<br> Duhamel, 2004). It has been hypothesized that gender perception takes place in higher level visual processing areas. Little, DeBruine, & Jones (2005) suggest that distinct neural<br> populations may code for subcategories of faces for which expertise-derived configural<br> processing is equivalent (i.e. male and female faces). They suggest that visual after-effects<br> are thought to reflect changes in the responses of neural mechanisms underlying face<br> processing and cannot be attributed to retinal (i.e. lower level) adaptations, as the after-effects<br> are robust to difference in the retinal location and size of faces at exposure and post-exposure<br> testing (Little, DeBruine, & Jones, 2005). In a study by Webster et al. (2004) categorical<br> perception of faces was examined based on gender, ethnicity and expression. Observers<br> made forced choice responses to categorize images along the continuum, for example<br> responding to whether a face from a gender morph appeared “female” or “male.” The<br> boundary for gender represents an androgynous image intermediate to the female and male<br> exemplars and could be set consistently by observers. However, after adapting to a male<br> face, the previously ambiguous image appeared distinctly feminine. Conversely, adaptation to<br> the female face induced the opposite changes. This effect is similar to results found in visual<br> after-effect studies. In a different investigation by Cellarino, Borghetti, and Sartucci (2004), the effect of pixilation on gender identification was conducted. As the photos became more pixilated the male faces were identified correctly more frequently than the female faces. This can be inferred to mean that male faces are composed of more lower frequencies since the pixilation wipes out the higher frequencies. The combination of these findings may suggest that the perception of gender can be influenced by lower level processes such as spatial frequency processing. </p></div></div> </div> </div

Lexical decision and the diffusion model: An investigation into the mental lexicon

<div> <div> <div> <div> <p>The lexical decision task is one of the most widely used tasks in psychology (Ratcliff, McKoon, & Gomez, 2004). Through the years, it has generally been used to investigate memory and lexical access (psycholinguistics). The lexical decision task is one way to study the organization and properties of the mental lexicon, how words are stored in the brain. The general assumption underlying the lexical decision task is that the speed and accuracy of responding to word stimuli indicate the efficiency with which word representations are activated or retrieved from lexical memory (Wangermakers, Zeelenberg, Steyvers, Shiffrin, Raaijmakers, 2004). </p> <p>By manipulating the variables by which words themselves differ or the ways in which they are presented, we can begin to shed light on these cognitive processes by analyzing and interpreting how these manipulations affect a subject’s reaction time and accuracy in classifying a string of letters as a word or not a word. Based on the data that is collected, models can be used to represent how these manipulations affect the cognitive processes and certain theoretical inferences can be made, specifically related to the metal representation of words in the mind and how words are categorized and stored in the mind (i.e. the mental lexicon). </p> <p>The factors that influence lexical access include word frequency, recency, and the presence of semantically related words and are all addressed in both types of models (search and network). By controlling and changing the variables of words or how they are presented, we can examine how these changes affect the timing of responses, which allows us to theorize about how these changes affect the processing in the mental lexicon. In three studies we manipulate the properties of words themselves, as well as manipulating conditions under which words are seen (priming) while subjects are performing a lexical decision task. We then fit the data from these investigations to the EZ Diffusion Model (Wagenmakers, van der Maas, & Grassman, 2007). By fitting the EZ diffusion to the results of the lexical decision task, do we gain insight to the cognitive processes of facilitation? The EZ diffusion may lend psychological plausibility of describing a response to manipulations of the lexical decision task. </p> </div> </div> </div> </div