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Age-related deficits in visual selective attention suggest that the efficiency of inhibitory processes is particularly affected by aging. To investigate whether processing inefficiencies observed in visual attention are similar in auditory attention and when shifting attention across modalities, we conducted an FMRI study with healthy young and older adults using a task that required sustained auditory and visual selective attention and cross-modal attention shifts. Older adults in this study performed as well as the younger adults, but showed age-related differences in BOLD responses. The most striking of these differences were bilateral frontal and parietal regions of significantly increased activation in older adults during both focused and shifting attention. Our data suggest that this increased activation did not reflect new recruitment, but reliance on brain regions typically used by younger adults when task demands are greater. Older adults' activation patterns suggested that even during focused attention conditions they were "shifting" attention to stimuli in the unattended modality. Increased activation during processing of both task-relevant and task-irrelevant information implies age-related loss of processing selectivity. These patterns may reflect both task-specific compensatory neural recruitment and degradation of sensory inhibition. 2Selective attention modulates sensory response to enhance selected relative to non-selected information. Electrophysiological studies have shown that the neural response in visual cortex is increased when visual information is attended (Heinze et al. 1994;Hillyard et al. 1998;Mangun et al. 1998). However, attention driven modulation of sensory cortex is not simple signal enhancement (gain), but also reflects neural specificity for the attended information that results from some combination of augmentation of selected and inhibition of non-selected or less relevant stimulation (Murray and Wojciulik 2004).While selective attention may remain grossly intact with normal aging, some components of attentional processing are affected. Hasher and Zacks (Hasher and Zacks 1988) proposed a model in which age-related deficits in attentional selectivity underlie changes in memory function. They suggested that an ineffective inhibitory system would allow irrelevant information into working memory buffers resulting in the association of large numbers of less specific memory traces. Additionally, an inefficient inhibitory system would affect the ability to suppress irrelevant pathways during memory retrieval and may reflect a central mechanism underlying both distractibility and memory deficits in older adults. A number of studies have suggested that there are age-related decreases in attention modulated neural specificity -most commonly observed as a decreased efficiency in the inhibition of unattended or less relevant information. Single cell recordings in senescent monkeys have shown significant reduction in selectivity of neurons in primary visual cortex that may reflect...

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Expertise in processing faces is a cornerstone of human social interaction. However, the developmental course of many key brain regions supporting face preferential processing in the human brain remains undefined. Here, we present findings from an FMRI study using a simple viewing paradigm of faces and objects in a continuous age sample covering the age range from 6 years through adulthood. These findings are the first to use such a sample paired with whole-brain FMRI analyses to investigate development within the core and extended face networks across the developmental spectrum from middle childhood to adulthood. We found evidence, albeit modest, for a developmental trend in the volume of the right fusiform face area (rFFA) but no developmental change in the intensity of activation. From a spatial perspective, the middle portion of the right fusiform gyrus most commonly found in adult studies of face processing was increasingly likely to be included in the FFA as age increased to adulthood. Outside of the FFA, the most striking finding was that children hyperactivated nearly every aspect of the extended face system relative to adults, including the amygdala, anterior temporal pole, insula, inferior frontal gyrus, anterior cingulate gyrus, and parietal cortex. Overall, the findings suggest that development is best characterized by increasing modulation of face-sensitive regions throughout the brain to engage only those systems necessary for task requirements.

When one is responding to targets containing a specific feature, non-predictive peripheral cues that share this feature lead to faster responses to the target, while cues that do not contain the target feature effectively are ignored, providing evidence for the role of attentional control settings (ACSs) in the contingent capture hypothesis. It is unclear, however, at what stage of processing multiple ACSs are implemented. We took advantage of the excellent temporal resolution of electroencephalography to demonstrate that the maintenance of multiple ACSs influences later stages of attentional selection rather than providing an early attentional filter. N2pc analyses for cues and targets revealed a similar degree of spatial capture for any peripheral cue, regardless of control settings, with target P3s reflecting the application of the ACS color contingencies.