Attentional blink in children with attention deficit hyperactivity disorder

Objective: To explore the temporal mechanism of attention in children with attention deficit hyperactivity disorder (ADHD) and controls using a rapid serial visual presentation (RSVP) task in which two letters (T1 and T2) were presented in close temporal proximity among distractors (attentional blink [AB]). Method: Thirty children aged between 9 and 13 years (12 with ADHD combined type and 18 controls) took part in the study. Both groups performed two kinds of RSVP task. In the single task, participants simply had to identify a target letter (T1), whereas in the dual task, they had to identify a target letter (T1) and a probe letter (T2). Results: The ADHD and control groups were equivalent in their single-task performance. However, in the dual-task condition, there were significant between-group differences in the rate of detection of the probe letter (T2) at lag + 1 and lag + 4. The ADHD group exhibited a larger overall AB compared with controls. Conclusion: Our findings provide support for a link between ADHD and attentional blink. .

Piscar atencional e as limitações do processamento de informações visuais conforme a frequência temporal / Attentional blink and the limitations of visual information processing related to temporal frequency

O sistema cognitivo possui capacidade limitada de processar informações, priorizando recursos atencionais a algumas, em detrimento de outras. A influência do tempo entre a apresentação de dois estímulos parece ser importante para esta seleção, pois dependendo do intervalo, a atenção ao primeiro prejudica a percepção do segundo. A este fenômeno chamou-se piscar atencional – PA. O objetivo desta revisão é apresentar o PA, descrever o paradigma utilizado para o seu estudo, as pesquisas que inicialmente o identificaram, os principais modelos teóricos que buscam explicar o fenômeno, bem como a sua relação com o efeito de priming semântico e com o processamento de estímulos emocionais. Os estudos mostram que os recursos atencionais são limitados também no domínio temporal e que a não percepção do segundo estímulo parece estar mais relacionada a uma limitação do controle da distribuição atencional, do que a uma falta de recursos propriamente dita. Além disso, esta limitação parece se relativizar conforme a classe de estímulos investigada. Conjuntamente, os achados discutidos demonstram a utilidade desta ferramenta experimental, a qual pode contribuir para o estudo de processos mentais e suas interações.

A Preliminary Study of Attentional Blink of Rapid Serial Visual Presentation in Burn Patients with Posttraumatic Stress Disorder

OBJECTIVES: Trauma patients have attentional bias which enforces traumatic memories and causes cognitive errors. Understanding of such selective attention may explain many aspects of the posttraumatic stress disorder(PTSD) symptoms. METHODS: We used the rapid serial visual presentation(RSVP) method to verify attentional blink in burn patients with PTSD. International affective picture system(IAPS) was used as stimuli and distracters. In the 'neutral test', patients have been presented series of pictures with human face picture as target stimuli. Each picture had 100ms interval. However the distance between target facial pictures was randomized and recognition of second facial picture accuracy was measured. In the 'stress test', the first target was stress picture which arouses patient emotions instead of the facial picture. Neutral and Stress tests were done with seven PTSD patients and 20 controls. In '85ms test' the interval was reduced to 85ms. The accuracy of recognition of second target facial picture was rated in all three tests. Eighty-five ms study was done with eighteen PTSD patients. RESULTS: Attentional blinks were observed in 100-400ms of RSVP. PTSD patients showed increased recognition rate in the'stress test' compared with the 'neutral test'. When presentation interval was decreased to 85 ms, PTSD patient showed decrease of attentional blink effect when target facial picture interval was 170ms. CONCLUSION: We found attentional blink effect could be affected by stress stimulus in burn patients. And attentional blink may be affected by stimulus interval and the character of stimulus. There may be some other specific mechanism related with selective attention in attentional blink especially with facial picture processing.