Since then, many studies have offered support for the notion that older individuals are less effective at inhibiting irrelevant information than their younger counterparts (e.g., Zacks and Hasher, 1994 Lustig et al., 2001). This so-called inhibitory deficit hypothesis was originally proposed by Hasher and Zacks (1988). A variety of common cognitive challenges in old age, such as memory decline, are thought to be the result of deficits in the inhibition of task-irrelevant information. Research into healthy cognitive aging has primarily focused on the latter mechanism: inhibition. This modulation takes place at two levels: (1) relevant stimuli are enhanced over other stimuli to facilitate processing of those stimuli and (2) processing of irrelevant stimuli is inhibited to avoid distraction. In contrast to bottom-up attentional modulation, which happens when an individual's attentional focus is passively drawn toward environmental, incoming stimuli, selective attention requires active selection, that is, facilitation of relevant and suppression of irrelevant stimuli, which is referred to as “top-down” attentional modulation. Because an individual can only attend to a limited portion of the environment, incoming stimuli need to be filtered. The strong need for this ability becomes apparent by considering the limited human processing capacity ( Miller, 1956). Selective attention enables a person to attend to relevant stimuli in the environment while ignoring irrelevant stimuli. Instead, they suggest that the underlying neural correlates of cross-modal selective attention are similar in younger and older adults. In conclusion, these results do not support the hypothesized age-related deficit of cross-modal auditory selective attention. cross-modal auditory selective attention was found in both age groups, which is consistent with earlier accounts of visual dominance. Moreover, stronger brain activation during cross-modal visual vs. Most importantly, activation throughout the brain did not differ across age groups, suggesting intact brain function during cross-modal selective attention in older adults. The imaging analyses showed that areas recruited by cross-modal visual and auditory selective attention in both age groups included parts of the dorsal attention and frontoparietal control networks (i.e., intraparietal sulcus, insula, fusiform gyrus, anterior cingulate, and inferior frontal cortex). Sixteen younger (mean age = 23.3 years) and 14 older (mean age = 65.3 years), healthy participants performed a series of delayed match-to-sample tasks, in which participants had to selectively attend to visual stimuli, selectively attend to auditory stimuli, or passively view and hear both types of stimuli, while undergoing 3T fMRI. For the first time, this study is taking on a whole brain approach while including a passive perception baseline, to investigate the neural underpinnings of selective attention across age groups, and taking the sensory modality of relevant and irrelevant (i.e., distracting) stimuli into account. Some of these investigations suggest a specific impairment of cross-modal auditory selective attention. 6Biological Psychology and Neuropsychology, Institute for Psychology, University of Hamburg, Hamburg, GermanyĪge-related deficits in selective attention have been demonstrated to depend on the sensory modality through which targets and distractors are presented.5Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands.4Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, Boston, MA, United States. ![]() 3Department of Psychiatry and Neuropsychology, Faculty of Health, Medicine and Life Sciences, School of Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands.2Department of Educational Development and Research, Faculty of Health, Medicine and Life Sciences, School of Health Professions Education (SHE), Maastricht University, Maastricht, Netherlands. ![]()
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