Age differences in motor suppression: Anelectromyographic study

Olga Puccioni, Antonino VallesiInternational School for Advanced Studies, SISSA, Trieste, Italy

Selective attention becomes less efficient with increasing age. Thepresent study investigated age differences in the ability to withhold amotor response to non-target stimuli. Fourteen healthy oldervolunteers (65–78 years, 8 F) and 14 younger controls (21–34 years,9 F) performed a go/nogo task, using red O and blue X as target gostimuli (50%), blue O and red X as high-conflict nogo stimuli (25%),and coloured numbers as low-conflict nogo stimuli (25%). Accuracy,response times (RTs), and electromyographic (EMG) activity from theextensor indicis of the right forearm were recorded. Older adultsmade significantly more commission errors to high-conflict nogostimuli (18.5%) than younger controls (8.7%) [t(26)=3, p<.01], thusindicating difficulty in refraining from responding when a relevantstimulus feature (letter identity) was shared with the go stimuli. Noage difference was observed in accuracy for low-conflict nogo stimuli(0.9 and 0.1% for older and younger adults, respectively). Finally,artifact-free root-mean-squared EMG activity (>4 standard devia-tions from the averaged pre-stimulus baseline for at least 8 ms) wasmore frequent in the older than in the younger group, not only onhigh-conflict nogo trials [35.6 vs. 17.9%; t(26)=4.15, p<.001], butalso on low-conflict nogo trials [11.6 vs. 6.3%; t(26)=2.56, p<.05],despite overt performance at ceiling. These findings demonstrate thatolder adults have difficulty in ignoring non-target material, evenwhen this is easily distinguishable from target information and overtperformance is at ceiling. The present study strongly supports theusefulness of complementing measures of overt performance withmore sensitive measures of covert motor activity, such as EMG inaging studies.

doi:10.1016/j.ijpsycho.2010.06.084

Psychophysiological responses to affective pictures in youngerand older adults

Patrick Gomeza, Armin von Guntenb,Leila Chouiterb, Brigitta Danuseraa Institute for Work and Health, University of Lausanne and University ofGeneva, Lausanne, Switzerlandb Service of Old Age Psychiatry of the Department of Psychiatry, CHUV,Lausanne, Switzerland

Introduction: The biphasic theory of emotion, according to whichemotion is fundamentally organized along the affective dimensions ofvalence (degree of pleasantness) and arousal (degree of activation),provided the theoretical framework for this study. In young adults,several neurophysiological measures such as heart rate have beenshown to covary with either reports of valence and arousal. Despitethe central role that basic emotional reactivity plays in adaptation,relatively few studies have examined age differences in this capacityunder well-controlled laboratory conditions, on the basis of standar-dized emotion-evoking stimuli, and assessing experiential, expres-sive, and physiological measures. The aim of this study was to extendour knowledge on the relationship between age and emotion acrossadulthood.

Method: In individual sessions, 212 adults ranging in age from20 to82 yearswere presentedwith 14 picture series, each lasting 60 s and ofa different thematic content (six expected to be pleasant, sixunpleasant and two neutral). We assessed cardiovascular, respiratoryand electrodermal measures, as well as facial muscle activity and gaze

activity. After each series, participants reported how they felt whilewatching the pictures by rating valence and arousal. Here, we presentthe findings for 22 younger (11 men, mean age=24.0, SD=2.8) and22 older (11 men, mean age=72.1, SD=4.4) adults on the followingmeasures: valence and arousal ratings, systolic blood pressure (SBP),and heart rate (HR)measured continuouslywith the Finometer device.

Results: Compared to younger adults, older adults rated unplea-sant series more negatively and showed a smaller range in arousal forpleasant series. SBP linearly increased with increasing appetitiveactivation both for younger and older adults, but did not increasewith increasing defensive activation either for younger or olderadults. HR showed the expected deceleration from the pleasant to theunpleasant series. However, this effect was clearer for the youngeradults than the older adults.

Conclusions: These findings give us indications on how psycho-physiological responses to affective stimuli may vary with age. Itappears that for older adults, if something is pleasant, it is judged tobe generally lower in arousal, whereas, if something is unpleasant, itis judged to be generally higher in arousal. The results for SBP, whichare mainly determined by sympathetic activation, indicate that theassociation between arousal and sympathetic outflow to thecardiovascular system might be fundamentally similar in youngerand older adults. In the context of picture viewing, increasing HRdeceleration with increasing unpleasantness is primarily due toincreasing parasympathetic activation to the heart. The results for HRsuggest that this parasympathetic activation might be attenuated inolder adults, as compared to younger adults.

doi:10.1016/j.ijpsycho.2010.06.085

Psychophysiological mechanisms of active longevity and theirgenetic correlates

D. Spivaka, A. Zakharchukb, T. Smirnovac, G. Yakupovac,V. Kupriyanovaa, I. Spivakca Human Brain Institute, Russian Academy of Sciences, St. Petersburg,Russiab St. Petersburg Municipal Gerontological Medico-Social Centre,St. Petersburg, Russiac Institute of Cytology, Russian Academy of Sciences, St. Petersburg,Russia

Based on the results of observation of 150 normal patients at ageriatric clinic, a number of fundamental regularities involved in theachievement of active longevity were revealed on the level ofpsychological processes and states and their genetic correlates.

Thus, the presence of a ‘defence centre’ that deals with age stresswas demonstrated; it includes basic psychological defence mechan-isms (i.e. negation, exclusion, regression, compensation, projection,substitution, intellectualization, reactive formation) and alteredstates of consciousness (as proposed by D. Spivak et al.) that act, inthis case, as a sort of supplementary psychological defence mechan-ism (for the latest English version of our questionnaire, see Gruzdev,Spivak, 2006; the nearest context of our test is provided by thefamous questionnaires of A.Dittrich et al., 1998 and R. vanQuekelberghe et al., 1991).

A positive link between prevalence of intrinsic religious orienta-tions by G. Allport (cf. Allport, 1967) and longevity was demon-strated, thus falling in line with a general thesis formulated in theframework of the psychological school of J. Kass (cf. Kass et al., 1991)that the aforementioned orientations have a role in counteracting‘stress-related components of illness’.

Finally, genetic correlates of active longevity and of intrinsicreligious orientations were traced back, linking both to the presence

260 Abstracts / International Journal of Psychophysiology 77 (2010) 239–287