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How cardiac components of the defense reaction are modulated by attentional factors related to sensory intake versus sensory rejection was examined. Forty-eight men participated in a test of the heart rate response to three presentations of an intense auditory stimulus while performing one of three attentional tasks during the 80 s following stimulus onset: (a) internal (rejection) task, (b) external (intake) task, and (c) no task. Results showed a potentiation of the defense response only under the external attention condition. We concluded that defensive reactions, far from provoking the rejection of the aversive stimulus, require allocation of attention to processing that stimulus in detail.

In relative positioning systems, with the aim of estimating object positions, distances among them are computed in a cooperative way, usually by measuring times-of-flight from the signals that they emit. These emissions are often synchronized with additional signals or suitable hardware that acts as a temporal reference. In this paper, a ranging system is presented where only acoustic emissions are used to compute the distances between objects or nodes. Thus, an organization and operation algorithm is proposed, which provides a temporal reference to the acoustic emissions carried out by every node. In this way, distances are computed by determining the temporal relation between a request of emission from a coordinator node and the corresponding answers emitted by the other nodes. In order to simultaneously detect the acoustic emissions, the signals are encoded with complementary set of sequences allowing multisensory operation and accepting low signal-to-noise conditions. With this measurement scheme, additional signals and high accuracy clocks often used for synchronization can be eliminated, thus reducing hardware complexity, power consumptions, and possible interferences with other systems (i.e. if radio frequency signals are used). The simulation and experimental results show that subcentimeter accuracy can be obtained with the proposed ranging scheme.

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A person-centred approach to assessing psychosocial and SWB configurations provides a rich picture of individual differences in the ageing processes and can help in designing interventions aimed at enhancing happiness in old age.

The cognitive and emotional modulation of the cardiac defense response was investigated in this study. One hundred forty-four participants were exposed to three presentations of an intense auditory stimulus while performing one of four attentional tasks: a control task, an external perceptual tracking task, and two internal tasks presented at either easy or difficult memory loads. State anxiety was also manipulated by requiring each group to perform either with or without the threat of shock. Heart rate and vasomotor activity were recorded. Results indicated that only the externally directed tracking task led to potentiation of the cardiac response. No predicted effects for attentional demands were obtained and the anxiety manipulation did not appear to have an effect. Differences between measures were also observed, particularly with respect to response habituation. Unlike cardiac activity, vasomotor responses displayed resistance to habituation. The results are discussed in relation to contemporary accounts of defensive responding.