Many event-related potential (ERP) studies have tried to find out which brain processes are responsible for the subjective experience of seeing. The contribution of these studies has been crucial in order to identify the temporal and spatial dynamics of visual awareness. The negative difference wave named visual awareness negativity (VAN), observed around 200 ms after the stimulus onset, has been claimed by many as a plausible candidate for reflecting the processes correlating with conscious visual perception. Other studies argue instead that only the P3 wave, a positive wave observed around 300-400 ms, correlates with visual awareness. The aim of the present study was to shed light on the issue of the presence of VAN even when using an experimental procedure that allows to dissociate the ERP correlate of subjective awareness from those of unconscious perception, allowing a separate analysis. Data from 24 participants was collected in the present study. The experimental framework included a forced-choice localization task of a low-contrast stimulus, followed by the subjective rating of awareness. The results of the study support the idea that the VAN is the earliest electrophysiological correlate of subjective visual awareness and that the phenomenon of visual awareness emerges early in the visual area.

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The results of 17 peer-reviewed studies utilizing morphological intervention were evaluated and compared in this meta-analysis. Participants included children from preschool to ninth-grade studying deep alphabetic, shallow alphabetic, or logographic (i.e., Chinese) orthographies. Cohen’s d was calculated to examine the effects of training on reading outcomes. Effects were analyzed according to child factors (ability level and age), intervention factors (agent, duration, frequency, setting, and group size), and orthographic factors. Additionally, effects were analyzed according to linguistic level (morphological, phonological, lexical, and supralexical) as well as group (experimental treatment group versus control group; experimental treatment group versus alternative treatment group) for the ability level, age, and orthography comparisons. Results indicate that (a) morphological training generally benefits students regardless of ability level and age; however, effectiveness varies per linguistic level, (b) with proper training and scaffolding, a variety of instructors can effectively implement morphological intervention, (c) the push-in school setting is generally the most effective setting, although gains were seen across all settings, (d) treatment was most effective when offered to individuals or large groups, (e) morphological intervention yield the greatest gains when lasting longer than one month, (f) it is effective for all types of orthographies. / text

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The topic ofsubliminalperception (perception without awareness) is investigated in this thesis. A technique of masking by visual noise was developed for use with an IBM-type microcomputer and VGA screen. This technique was used to investigate whether subliminal mood priming influences subjects' resolution oflexical ambiguity in a homophone task designed by Halberstadt et al. (1995). Limited evidence was found for mood-congruent priming, but only for negative emotional priming, and with the most strongly negative items. Some non-specific effects were also found to be associated with negative mood priming. The mood-priming effect was correlated with the negative emotional ratings of these items obtained from a separate group ofsubjects. In a Follow-up study, a self-report mood scale was used to assess subjects' reaction to both negative and positive subliminal stimuli. A pattern oftrends was found which suggested that subjects experienced a paradoxical improvement in mood after exposure to the negative stimulus. No changes were observed in the group exposed to the positive stimuli. A theoretical explanation was entertained which suggested that subjects adaptively attributed their change in affective arousal in terms of experimental demands. of A number ofrelationships to recent research were suggested by these experiments, in particular the finding of a preattentive bias for negative information in subjects with anxiety and non-clinical depression by Bradley et al., (1994, 1995) and Mogg et al.,(1993). It is suggested that measures ofphysiological and cortical arousal should receive attention in future research in order to clarify the response to subliminal stimulation in terms of affective arousal. / Thesis (M.A.)-University of Natal, Pietermaritzburg, 1997.

In 2 experiments, we taught 120 3-year-olds and 120 adults novel words for unfamiliar solid objects or perceptually similar nonsolid substances described as belonging either to the toy domain or the food domain. In a forced-choice task, participants extended the novel words to one of two test items: a same-shape test item (i.e., one that shared a common shape with the standard but differed in colour, texture, or smell) or a same-substance test item (i.e., one that shared a common colour, texture, and smell with the standard but differed in shape). Participants made more same-shape choices in the solid than in the nonsolid conditions. This tendency varied depending on whether the same-shape item differed from the standard in colour, texture, or smell. Participants also made more same-shape choices for items described as toys than for the same items described as food. This tendency was consistent regardless of whether the same-shape item differed from the standard in colour, texture, or smell. The findings confirm previous reports that children's word extensions are affected by the solidity of the referent. They also reveal that these extensions are guided by information about the referent's conceptual domain. Finally, these results provide the first evidence that these extensions are influenced by the smell, texture, and colour of the referent.

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Increased impulsivity and alterations in reward sensitivity co-occur in many psychiatric disorders. Moreover, individuals reporting more impulsive traits are less efficient in learning stimulus-reward associations. This suggests that impulsivity and reward sensitivity may be linked, consistent with evidence that the orbital frontal cortex (OFC) is implicated in both processes. This study examined the relationship between impulsive traits, assessed by the Barratt Impulsiveness Scale (BIS) and the Eysenck (EIQ), and performance on three behavioral tasks that measure impulsivity and reward sensitivity. The tasks included a Conditioned Pattern Preference (CPP) task, which measures the preference for abstract visual cues as an index of implicit emotional learning, a Probabilistic Reversal Learning (PRL) task that assessed the ability to alter behaviour when reward contingencies change and an Emotional Stroop task which assessed attentional control in response to emotionally salient stimuli. This study provided novel information on the relationship between processes that mediate impulsivity and reward sensitivity. In brief, subjects that were considered to have some explicit knowledge of experimental conditions showed a higher preference formation for the pattern paired with the reward on 90% of the conditioning trials. Although there was no overall effect of impulsivity, the medium impulsive group displayed the strongest preference formation (highest score for the 90% pattern and lowest score for the 10% pattern) compared to the low and high groups. Furthermore, there was an overall effect of Word Category in that participants made more errors for the emotional words (positive and negative) than the neutral words. There was no overall effect of Impulsivity on Stroop performance in this sample. Finally, for the PRL task more participants in the high impulsive group did not meet criterion for the Acquisition stage while more low impulsive subjects did not meet reversal criterion. Furthermore, high impulsive subjects made more overall errors in the Acquisition stage but not Reversal stage. In brief, low and high impulsive subjects performed sub-optimally on the CPP and PRL tasks but not on the Stroop task. This pattern reflects an inverted-U shaped relationship of the effects of impulsivity on associative learning. / Thesis (Master, Psychology) -- Queen's University, 2010-02-05 13:33:27.076

This study evaluates beginner readers on three aspects of metalinguistic awareness as measured by Metalinguistic Awareness Interview Schedule (Dreher & Zenge, 1990), the understanding of reading as a meaning-gathering process; the ability to isolate language segments (sentences, words and letters); knowledge of terms used in reading instruction, as well as some basic concepts about print, as measured by the adapted Concepts About Print test (Clay, 1979). Individual interviews were conducted with a socioculturally diverse group of first grade pupils attending two schools on the Upper South Coast of KwaZulu Natal. Whilst considering the performance of the group as a whole, attention was also given to the three different language culture subgroups, and to second language learners who represented 40% of the sample. Consistent with earlier research carried out in other countries the results of this study confirmed that many of these beginner readers had only demonstrated a partial acquisition of metalinguistic abilities and a limited understanding of concepts about print as assessed by the two measurements. These confusions were described and their implications for teaching practice discussed. At the end of the subjects' grade one year a follow-up procedure was conducted to examine academic achievement in various aspects of English, and in Mathematics. In addition, readiness for grade two was also considered. These results indicated that much of the earlier confusion as demonstrated on the two measurement instruments had been resolved through instruction and mediation in the classroom. The implications of the findings, the limitations of the study and some suggestions for further research are discussed. / Thesis (M.Ed.) - University of Natal, Pietermaritzburg, 1996.

Developmental dyslexia is widely believed to be caused either mainly or in part by an impairment of phonological representations. Although this hypothesis predicts that individuals with dyslexia should show deficits in tasks which require the use of implicit phonological knowledge, this has not yet been directly tested, as the evidence cited in support of this hypothesis usually comes from metalinguistic tasks which demand explicit awareness of phonological units. Additionally, since the ability to perform metalinguistic tasks which involve phonological segments can be enhanced by an individual’s competence in alphabetic literacy, the possibility remains that phonological skills may have been inadequately isolated from the influences of literacy acquisition in many cases. The study reported in this thesis investigated both the representations and the metalinguistic skills of a group of adults with a history of developmental dyslexia, examining areas of phonology which do and do not have orthographic counterparts. To isolate phonological skills from orthographic skills, the representations of conventional segmental contrasts (e.g. /k/ vs /g/) were compared with the representation of suprasegmental contrasts (as seen in minimal pairs such as ′toy factory and toy ′factory), which have no orthographic counterpart. Basic metalinguistic skills were tested by means of a phonological awareness task targeting both segmental and suprasegmental units, and phonological manipulation skills were tested using a Pig Latin task and a Spoonerism task, where participants were required to manipulate both segmental and suprasegmental units (e.g. extracting the segment /b/ from consonant clusters and the main stress from SWW or WSW stress patterns). The results showed that although the performance of the dyslexic group was weaker than that of the control group when tasks required the manipulation of either the segmental or suprasegmental components of words, no evidence was found for a deficit in the tasks which drew on implicit representations or basic metalinguistic skills. These findings suggest that the phonological deficit in dyslexia may be restricted to the ability to manipulate phonological units rather than in the representation of them per se.