Automatic auditory and somatosensory brain responses in relation to cognitive abilities and physical fitness in older adults

Abstract

In normal ageing, structural and functional changes in the brain lead to an altered processing of sensory stimuli and to changes in cognitive functions. The link between changes in sensory processing and cognition is not well understood, but physical fitness is suggested to be beneficial for both. We recorded event-related potentials to somatosensory and auditory stimuli in a passive change detection paradigm from 81 older and 38 young women and investigated their associations with cognitive performance. In older adults also associations to physical fitness were studied. The somatosensory mismatch response was attenuated in older adults and it associated with executive functions. Somatosensory P3a did not show group differences, but in older adults, it associated with physical fitness. Auditory N1 and P2 responses to repetitive stimuli were larger in amplitude in older than in young adults. There were no group differences in the auditory mismatch negativity, but it associated with working memory capacity in young but not in older adults. Our results indicate that in ageing, changes in stimulus encoding and deviance detection are observable in electrophysiological responses to task-irrelevant somatosensory and auditory stimuli, and the higher somatosensory response amplitudes are associated with better executive functions and physical fitness.

Event-Related Potentials to Changes in Sound Intensity Demonstrate Alterations in Brain Function Related to Depression and Aging

“…As expected, an age-related effect was found for sensory gating. Older adults had larger N1 amplitudes to both highand low-intensity standard sounds compared to younger adults, which aligns with previous studies (Anderer et al, 1996;Amenedo and Díaz, 1998;Alain and Woods, 1999;Strömmer et al, 2017) and suggests a deficit of inhibitory control (Friedman, 2011). In addition to enlarged N1 responses to standard sounds, the older adults displayed larger N1 responses to rare high-intensity sounds.…”

“…For N1 sensory gating, responses to both standard and deviant sounds (see also Anderer et al, 1998;Tusch et al, 2016;Strömmer et al, 2017) for the conditions (increment and decrement) were included. For standard sounds, only responses to pre-deviant standards were included in the analysis because they had been repeated at least twice and therefore enabled an examination of the neural suppression related to stimulus repetition.…”

“…Much shorter SOAs were not possible, because there could be ongoing activity related to MMN and P3a components approximately at 150-250 ms (Näätänen et al, 1978(Näätänen et al, , 2007 and 250-500 ms (Squires et al, 1975;Polich, 2007) latency after stimulus onset, respectively, that would be present at the baseline with a short SOA. Similar SOAs to those applied here has been used in previous studies of sensory gating (Strömmer et al, 2017), intensity dependence (Linka et al, 2007;Park et al, 2010;Lee et al, 2014) and MMN (He et al, 2010;Naismith et al, 2012;Chen et al, 2015;Ruohonen and Astikainen, 2017).…”

“…Oddball conditions have also been used to study sensory gating. In such studies, a sensory gating deficit in older adults is indicated by larger N1 responses to repeated sounds in older compared to younger adults (Anderer et al, 1996;Amenedo and Díaz, 1998;Alain and Woods, 1999;Strömmer et al, 2017; for a review, see Friedman, 2011; for absent group difference, see Gaeta et al, 1998;Čeponiene et al, 2008). Although sensory gating deficit has also been associated with some neuropsychiatric disorders such as schizophrenia and bipolar disorder (Boutros et al, 1999(Boutros et al, , 2004Lijffijt et al, 2009), the evidence on depression is scarce (see however, Baker et al, 1990;Wang et al, 2009).…”

“…Intensity changes will be presented in an oddball condition; which enables the investigation of sensory gating, intensity dependence and MMN within the same experiment. As mentioned above, sensory gating deficit has been demonstrated in aging (Anderer et al, 1996;Amenedo and Díaz, 1998;Alain and Woods, 1999;Strömmer et al, 2017; for a review, see Friedman, 2011), and intensity dependence may be a relevant marker for depression (Gopal et al, 2004;Fitzgerald et al, 2009;Lee et al, 2014). Furthermore, deficits in auditory change detection as indexed by MMN have been associated with both aging (Czigler et al, 1992;Schroeder et al, 1995;Gaeta et al, 1998;Alain and Woods, 1999;Cooper et al, 2006;Čeponiene et al, 2008) and depression (Kähkönen et al, 2007;He et al, 2010;Naismith et al, 2012;Qiao et al, 2013;Chen et al, 2015;Restuccia et al, 2016).…”