Latencies in BOLD response during visual attention processes

• Published in: Brain research Vol. 1386; pp. 127 - 138
• Main Authors: Kellermann, Thilo, Reske, Martina, Jansen, Andreas, Satrapi, Peyman, Shah, N. Jon, Schneider, Frank, Habel, Ute
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 22.04.2011; Elsevier
• Subjects: Adult; Arousal; Arousal - physiology; Attention; Attention - physiology; Biological and medical sciences; BOLD latency; cognition; Cues; Eye and associated structures. Visual pathways and centers. Vision; Female; fMRI; Functional Laterality; Functional Laterality - physiology; Fundamental and applied biological sciences. Psychology; Gyrus Cinguli; Gyrus Cinguli - physiology; Humans; magnetic resonance imaging; Male; Neurology; Neurons; Neurons - physiology; physiology; Reaction Time; Reaction Time - physiology; thalamus; Vertebrates: nervous system and sense organs; Visual Pathways; Visual Pathways - physiology; Visual Perception; Visual Perception - physiology; Young Adult; fMRI; BOLD latency; Attention; Human; Vision; Perception; Cognition; Visual attention; Nuclear magnetic resonance imaging; Functional imaging
• ISSN: 0006-8993; 1872-6240; 1872-6240
• DOI: 10.1016/j.brainres.2011.02.023

One well-investigated division of attentional processes focuses on alerting, orienting and executive control, which can be assessed applying the attentional network test (ANT). The goal of the present study was to add further knowledge about the temporal dynamics of relevant neural correlates. As a right hemispheric dominance for alerting and orienting has previously been reported for intrinsic but not for phasic alertness, we additionally addressed a potential impact of this lateralization of attention by employing a lateralized version of the ANT, capturing phasic alertness processes. Sixteen healthy subjects underwent event-related functional magnetic resonance imaging (fMRI) while performing the ANT. Analyses of BOLD magnitude replicated the engagement of a fronto-parietal network in the attentional subsystems. The amplitudes of the attentional contrasts interacted with visual field presentation in the sense that the thalamus revealed a greater involvement for spatially cued items presented in the left visual field. Comparisons of BOLD latencies in visual cortices, first, verified faster BOLD responses following contra-lateral stimulus presentation. Second and more importantly, we identified attention-modulated activation in secondary visual and anterior cingulate cortices. Results are discussed in terms of bottom-up and lateralization processes. Although intrinsic and phasic alertness are distinct cognitive processes, we propose that neural substrates of intrinsic alertness may be accessed by phasic alertness provided that the attention-dominant (i.e., the right) hemisphere is activated directly by a warning stimulus. ► We investigated latency and amplitude differences in BOLD responses. ► The task consisted of a lateralized version of the attentional network test. ► Lateralized presentation of stimuli led to delays in ipsilateral visual areas. ► Cueing of visual stimuli led to earlier responses in secondary visual cortices. ► Spatially cued items presented in the left visual field engaged the thalamus.