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- P-ISSN1226-9654
- E-ISSN2733-466X
- KCI
ISSN : 1226-9654
Vol.28 No.1
Abstract
The present study examined whether Korean learners of English use grapheme-to-phoneme correspondence rule as in native English speakers during English word recognition. In visual word recognition, both word frequency and regularity play a major role in reading speed and reading accuracy. Hence, the purpose of this study was to investigate how spelling-to-sound regularity and word frequency influence performance on explicit reading and silent reading tasks among English second language learners. Previous word recognition studies with English monolinguals have reported word regularity effect, in which regular words(e.g., save) are recognized faster with lower error rates compared to irregular words(e.g., have). Word regularity effect has been widely used as the supporting evidence for dual route model in visual word recognition. In Experiment 1, an explicit reading task(English word naming task) was used to examine the presence of word regularity effect during read-aloud process. In Experiment 2, a silent reading task(lexical decision task) was administered to examine the influence of irregularities in spelling and sound when participants were not required to generate sound information from spellings during English word recognition. Results from Experiment 1 demonstrated a significant interaction between word frequency and regularity, where word frequency effect was significant in all experimental conditions. On the other hand, word regularity effect showed marginal significance in low frequency word condition only. Results from Experiment 2 only revealed a significant word frequency main effect. Overall, these results indicate that Korean English L2 learners also seem to be able to use spelling-to-sound information during English word recognition similar to those of English monolinguals. However, rather than actively making use of this information via phonological(indirect) route, they have the tendency to use lexical(direct) route which is more sensitive to spelling information. The current study re-evaluated the English word regularity effect among Korean learners of English in terms of their use of spelling-to-sound information during English word recognition.
Abstract
We examined whether attention is biased toward smartphone-relevant visual cues in smartphone addictive tendencies. Based on a survey of Smartphone Addiction Scale(NIA, 2011), participants (n=42) were categorized into either normal control or addiction tendency group. Participants of each group carried out comparison blindness task which consisted of three classes of different stimulus combinations(smartphone changed(SC), neutral changed(NC), & smartphone absent(SA) visual stimuli). Then, we measured response time and accuracy while accomplishing a comparison blindness task, and we compared performance (change detection) of participants between SC and NC condition. As results, the tendency-group showed significantly faster response time under SC condition than NC condition. Next, the tendency-group showed significantly faster response time than control-group under SC condition, and the tendency-group showed significantly slower response time than control-group under NC condition. Consistent with (Similar to) previous studies, relevant-stimuli give rise to attentional bias in smartphone addictive tendencies. Consequently, the results suggest that addiction characteristics are manifested in smartphone addictive tendencies.
Abstract
In selective attention tasks such as the Stroop or flanker tasks, performance on the current trial is modulated by trial sequence. This is referred to as the conflict adaptation (CA) effect, which is used for a measurement of cognitive control. Various theoretical accounts have been proposed to explain the CA effect in a top-down or bottom-up manner. In a top-down attentional modulation view, the conflict monitoring theory suggests reactive control whereas a expectation-based account proposes proactive control. These have different assumption in the time-course of the CA effect. In the present study, we used a relatively difficult version of the Stroop task to investigate whether the CA effect is influenced by temporal operation in the light of proactive control. In the Experiment 1 and 2, diverse inter-stimulus intervals were randomly presented in the tasks. The result showed that the CA effect could occur proactively when the processing time was sufficient. In the Experiment 3, we manipulated the inter-stimulus intervals in the block design to facilitate participants' anticipation of the stimulus presentation time. The results demonstrated that proactive control could be enhanced due to the expectation effect. Our findings suggest that the CA effect could occur through proactive control according to the nature of tasks. In addition, proactive control appears to operate more efficiently when processing time is enough and prediction of the stimulus onset is easy.
Abstract
This study investigated deficits of facial affect recognition in college students with schizotypal traits using event-related potentials (ERPs). Based on the scores of Schizotypal Personality Questionnaire (SPQ), control (n=20) and schizotypal-trait groups (n=20) were selected. The ability of face identification was evaluated with a face-building discrimination test, in which participants were required to distinguish the pictures of human face and building. A facial affect recognition task, in which participants were required to distinguish faces exhibiting positive, negative or neutral emotion, was used for the measurement emotional recognition ability. The results of face-building discrimination task showed that the control and schizotypal-trait groups did not differ significantly in terms of response time and accuracy rate. In addition, the two groups did not differ in N170 amplitude that reflects the structural encoding of face. However, schizotypal-trait group exhibited more errors for negative valence than did the control group, and the two groups showed different ERP patterns in the facial affect recognition task. The control group showed significantly larger N250 amplitudes in response to emotional stimuli than to the neutral ones, whereas schizotypal-trait group exhibited no significant differences in N250 amplitudes between emotional and neutral faces. These findings suggest that individuals with schizotypal traits have difficulties in facial affect recognition, which could be served as a trait marker for schizospectrum disorders.
Abstract
Attentional functions are revealed to be impaired in individuals with schizophrenia. However, as attention is a multi-dimensional function, various studies have investigated different types of attentional deficits among patients with schizophrenia. The purpose of this review is to take a comprehensive look at evidence on distinctive aspects of attentional impairments in schizophrenia. Three different domains of attention are of interest in this review: Response inhibition, Selective attention and Conflict resolution, and Attentional shifts and Alerting networks. A number of studies with schizophrenia suggest that the selective attention and conflict resolution are most affected in those patients. The disengagement and attentional reorienting system also seems to be impaired in the patients. In this review, findings from behavior, neuroimaging, and electrophysiological studies are discussed to understand fundamental attentional deficits in patients with schizophrenia. The future direction of studies aiming to elucidate and treat those patients’ attentional mechanism is also discussed.
Abstract
The present study compared the effect of eye movements on postural control in 13 Parkinson’s disease (PD) patients (Hoehn-Yahr stage 2-3) and 13 age-matched healthy adults. Participants viewed, from a distance of 1 m, a computer display of an oscillating object that continuously changed shape and reported the number of times the shape changed over each 60 s trial. Four oscillation rates (0, 0.5, 0.8, and 1.2Hz) were presented. Postural sway data (mean position, standard deviation, and range of the excursions in the anterior-posterior and medio-lateral directions) were obtained using a wireless motion tracking system via sensors attached to each participant’s head, neck, and cervical spine. The effect of eye movement frequency on postural sway was minimal in the healthy adults, consistent with the view that postural control and suprapostural task (eye movement control) are functionally integrated to facilitate the performance of suprapostural control tasks. By contrast, PD patients’ showed greater and more variable postural sway, particularly in the anterior-posterior direction. It appears that PD patients’ impaired postural control systems are no longer integrated functionally with their eye movement control. This result suggests an additional factor to consider in PD patients who are susceptible to falls due to postural instability.
Abstract
Midbrain dopamine neurons exhibit diverse responses to aversive stimuli, such as foot and tail shocks. Specifically one group of dopamine cells is phasically inhibited by the stimuli, whereas the other group is excited. A previous report indicated that mice whose dopamine neurons were genetically modified to disrupt the excited, but not inhibited, response to a shock exhibited generalized anxiety behavior after experiencing fearful events. Thus, it was hypothesized that an increase in dopaminergic excitation improved discriminatory fear learning. To test this idea, mice were trained in a discriminatory fear conditioning paradigm where one auditory conditioned stimulus (CS+) was paired with aversive footshock and the other tone (CS-) was not paired. Dopamine neurons in the ventral tegmental area were optogenetically stimulated during the presentation of one of the two CSs. The intensity of the footshock was strong enough for control mice to show generalized fear responses to both CSs. However, dopamine-stimulated mice was able to discriminate between two CSs, so that they freezed more time in response to CS+ than to CS-. These results suggest that dopamine neurons contribute to fear discrimination.
Abstract
Conflict adaptation refers to a phenomenon in which the congruency effect decreases in an incompatible trial followed by the same incongruent trial in conflict tasks(Gratton & Donchin, 1992). This study measured whether conflict adaptation occurs upon the process of two conflicting stimuli within a trial, and whether a certain pattern of conflicts within a trial affects the performance in the next trial. The participants performed a Stroop comparison task, whrere they compared the meaning of one of the two presented Stroop words with the color of the other word. In Experiment 1, two Stroop words with distinctive task-relevant information were presented in sequence. The congruency effects of the second stimulus were analyzed as contingent on congruency of the previous stimuli. The results showed that the conflict adaptation effects which the second Stroop stimuli yielded reduced the congruency effect when the first Stroop word was incongruent. In Experiment 2, conflict adaptation between trials was observed when two Stroop words were shown simultaneously. The pattern of conflicts within a trial was one of four conditions determined by the relation with each stimulus’ congruency; congruent-congruent, congruent- incongruent, incongruent-congruent, and incongruent-incongruent. The results showed that the RT on current trials decreased when the pattern of conflicts in the current trial was identical to the previous trial. The complex pattern of conflicts generated by the previous trial affected the performance for the next trial. In conclusion, this study newly found the conflict adaptation within a single trial, which was sequentially processed and responded to two stimuli, and the effects of the complex pattern of the conflicts within a trial on the conflict adaptation in the following trial.
Abstract
The Flashed Face Distortion Effect (FFDE) refers to the face images look grotesque and distorted when they are presented quickly and continuously in the periphery of visual field (Tangen, Murphy, & Thompson, 2011). While Tangen et al. (2011) suggested that the relative encoding of facial components is responsible for the FFDE, this was not empirically tested. To test this, we conducted three experiments to investigate the conditions evoking FFDE. In Experiment 1, we investigated the effect of presentation duration, presentation number, and total time on the FFDE. In Experiment 2, we examined the effects of the spatial distance among internal features and repeated presentation on FFDE. In Experiment 3, we investigated the effects of change of the spatial distance among internal feature, the change of the shape of internal features, and whether the external features on FFDE are the same or different. The results showed that the effects of presentation duration and number were affected by the total time. The spatial distance among internal features and repeated presentation did not affect the illusion, However, we found the illusion was stronger in the condition that the spatial distance among internal features was smaller than the condition that the spatial distance among internal features was lager when the external feature was same. These findings suggest that the FFDE is connected with crowding effect rather than relative encoding among faces.
Abstract
When participants are asked to identify two targets embedded in a rapid serial visual presentation (RSVP), they hardly identify the second target that is presented within 200-500ms after the first target. This is called an attentional blink (AB). A recent study reported that AB can be removed by the color-salient training in which the second target within 200-500ms is presented in a salient color. The study suggested that the training effect is caused by an improvement of our attentional control mechanism, which is responsible for both target selection and distractor inhibition. Alternatively, however, the training effect might be understood as a result of visual perceptual learning evoked by repetitive exposure to stimuli during the training. The current study tested these two hypotheses through an experiment that consisted of four sessions: a pre-test session, two color-salient training sessions, and a post-test session, in that order. All sessions employed number targets and alphabet letter distractors in RSVP. During the training, only half of eight numbers (from 2 to 9) were randomly selected as targets. Our results showed that even when untrained numbers, which were not used in the training, were employed as targets in the post-test, the training effects occurred, resulting in removal of AB. It supported the hypothesis that the color-salient training effect occurs not as a result of the visual perceptual learning but as a result of improvement in our attentional capacity.
Abstract
The present study investigated whether visual discomfort was influenced by various individual differences, such as age, motion sickness susceptibility, interpupilary distance, and stereo acuity. The last three characteristics were measured individually. After watching 3D television programs for 80 minutes, participants answered the visual discomfort questionnaire, consisting of 5 different factors such as dizziness, eye pain, body ache, blurring vision. The university students and young adults had more discomfort than the participants in their 30s, 40s, or older. For the participants in their 20s, observers with higher scores in motion sickness susceptibility had more discomfort, but this tendency was weakened and disappeared as observers' age increased. With regard to interpupilary distance and stereo acuity, there was no difference in visual discomfort. The results were discussed in the context of convergence-accommodation conflict in 3D environment.