Search results for "Discrimination"
showing 10 items of 477 documents
Mismatch negativity (MMN) as a tool for investigating auditory discrimination and sensory memory in infants and children
2000
For decades behavioral methods, such as the head-turning or sucking paradigms, have been the primary methods to investigate auditory discrimination, learning and the function of sensory memory in infancy and early childhood. During recent years, however, a new method for investigating these issues in children has emerged. This method makes use of the mismatch negativity (MMN), the brain's automatic change-detection response, which has been used intensively in both basic and clinical studies in adults for twenty years. This review demonstrates that, unlike many other components of event-related potentials, the MMN is developmentally quite stable and can be obtained even from pre-term infants…
Amusic does not mean unmusical: Beat perception and synchronization ability despite pitch deafness
2013
Pitch deafness, the most commonly known form of congenital amusia, refers to a severe deficit in musical pitch processing (i.e., melody discrimination and recognition) that can leave time processing--including rhythm, metre, and "feeling the beat"--preserved. In Experiment 1, we show that by presenting musical excerpts in nonpitched drum timbres, rather than pitched piano tones, amusics show normal metre recognition. Experiment 2 reveals that body movement influences amusics' interpretation of the beat of an ambiguous drum rhythm. Experiment 3 and a subsequent exploratory study show an ability to synchronize movement to the beat of popular dance music and potential for improvement when give…
Discrimination, work and health in immigrant populations in Spain
2009
One of the most important social phenomena in the global context is the flow of immigration from developing countries, motivated by economic and employment related issues. Discrimination can be approached as a health risk factor within the immigrant population's working environment, especially for those immigrants at greater risk from social exclusion and marginalisation. The aim of this study is to research perceptions of discrimination and the specific relationship between discrimination in the workplace and health among Spain's immigrant population. A qualitative study was performed by means of 84 interviews and 12 focus groups held with immigrant workers in five cities in Spain receivin…
Size invariance in visual number discrimination
1991
This study deals with the observer's ability to discriminate the numerosity of two random dot-patterns irrespective of their relative size. One of these two patterns was a reference one that was always composed of 32 dots randomly distributed within a K x K invisible square window (K = 1.92 degrees). The second one was the test pattern with one of the five magnifications (K = 0.64 degrees, 1.28 degrees, 1.92 degrees, 2.56 degrees, 3.20 degrees) and the relative number of dots varied on 11 levels (N = -15, -12, -9, -6, -3, 0, 3, 6, 9, 12, or 15 dots). The observer's task was to indicate which of the two patterns contained more dots. The results show that the stimulus size, as an irrelevant s…
Event-Related Potentials and Autonomic Responses to a Change in Unattended Auditory Stimuli
1992
Event-related brain potentials (ERPs) and autonomic nervous system (ANS) responses to occasional pitch and rise-time changes in a task-irrelevant auditory stimulus repeating at short intervals were measured while the subject performed a difficult intellectual task (Raven Matrices). It was found that deviant stimuli elicited the mismatch negativity (MMN) component of the ERP even when they elicited no ANS response. There was no significant difference in the mismatch negativity between trials in which the skin conductance response was or was not elicited. The pitch deviant tone also elicited heart rate deceleration, whereas the rise-time deviant tone tended to elicit a later heart rate accele…
Prismatic lenses shift time perception
2009
Previous studies have demonstrated the involvement of spatial codes in the representation of time and numbers. We took advantage of a well-known spatial modulation (prismatic adaptation) to test the hypothesis that the representation of time is spatially oriented from left to right, with smaller time intervals being represented to the left of larger time intervals. Healthy subjects performed a time-reproduction task and a time-bisection task, before and after leftward and rightward prismatic adaptation. Results showed that prismatic adaptation inducing a rightward orientation of spatial attention produced an overestimation of time intervals, whereas prismatic adaptation inducing a leftward…
Illusory contours from pictorially three-dimensional inducing elements: counterevidence for Parks and Rock's example.
1993
In 1990 Parks and Rock claimed that, in pictorially three-dimensional (3-D) inducing patterns, an illusory figure does not emerge if a clear occlusion event is not present. A new pictorially 3-D pattern is presented which contradicts this claim. Two experiments were carried out. The first was aimed at ascertaining the presence of an illusory figure in the new 3-D pattern; the second was aimed at offering evidence that in Parks and Rock's pattern the disappearance of the illusory figure could be due to local interferences caused by the line elements in contact with the inducing borders. The results tend to contradict Parks and Rock's conclusions.
Sex differences in conditioned stimulus discrimination during context-dependent fear learning and its retrieval in humans: the role of biological sex…
2015
BACKGROUND: Anxiety disorders are more prevalent in women than in men. Despite this sexual dimorphism most experimental studies are conducted in male participants and studies focusing on sex differences are sparse. In addition the role of hormonal contraceptives and menstrual cycle phase in fear conditioning and extinction processes remain largely unknown. METHODS: We investigated sex differences in context-dependent fear acquisition and extinction (day 1) and their retrieval/expression (day 2). Skin conductance responses (SCRs) fear and unconditioned stimulus expectancy ratings were obtained. RESULTS: We included 377 individuals (261 women) in our study. Robust sex differences were observe…
Selecting one of two regular sound sequences : Perceptual and motor effects of tempo
2008
This study assessed the influence of tempo on selecting a sound sequence. In Exp. 1, synchronization with one of the two regular subsequences in a complex sequence was measured. 30 participants indicated a preference for the fastest subsequence when subsequences were in a slow tempo range (≥ 500 msec. IOI), and with the slower subsequence when they were in the fast tempo range (≤ 300 msec. IOI). These results were replicated using a perceptual task (Exp. 2 and 3) in which the 30 listeners had to detect a temporal irregularity in one of the two subsequences. Detection was better when the temporal irregularity was in the fastest subsequence than in the slowest one when the complex sequence w…
Generalization gradients for fear and disgust in human associative learning
2021
AbstractPrevious research indicates that excessive fear is a critical feature in anxiety disorders; however, recent studies suggest that disgust may also contribute to the etiology and maintenance of some anxiety disorders. It remains unclear if differences exist between these two threat-related emotions in conditioning and generalization. Evaluating different patterns of fear and disgust learning would facilitate a deeper understanding of how anxiety disorders develop. In this study, 32 college students completed threat conditioning tasks, including conditioned stimuli paired with frightening or disgusting images. Fear and disgust were divided into two randomly ordered blocks to examine di…