An experimental test of the relationship between voice intonation and persuasion in the domain of health

Objective: In the process of behaviour change, intonation of speech is an important aspect that may influence persuasion when auditory messages are used. In two experiments, we tested to what extent different levels of intonation are related to persuasion and whether for some recipients the threat posed by the message information might become too strong to face.

Design: In Study 1, 130 respondents listened to a health message with either a low, moderate or high level of intonation. In Study 2 (N?=?143), the same manipulations of intonation were applied but half of the respondents were affirmed before they listened to the persuasive message. Intention to increase fruit and vegetable intake was used as a dependent variable.

Results: Both studies showed that high intonation led to a significant drop in intention among respondents who perceived their own health as good. After self-affirmation, persuasion was increased.

Conclusion: A high level of intonation seems to induce self-regulatory defences in people who do not see the necessity to change their health behaviour, whereas people with poor perceived health might perceive potential to change. The use of a normal level of intonation in auditory health messages is recommended.     

The Differential Outcomes Effect

The Psychological Record - The differential outcomes effect refers specifically to the increase in speed of acquisition or terminal accuracy that occurs in discrimination training when each of two...     

BIOFEEDBACK OF EVENT-RELATED SLOW POTENTIALS OF THE BRAIN

A biofeedback paradigm was developed for self-regulation of cortical DC-shifts. Subjects received continuous visual feedback of their actual DC-shift during six sec. intervals. Feedback trial series alternated with transfer test trial series. Several studies demonstrated that subjects are able to achieve cortical self-regulation which is maintained and even improved in transfer test trials. This method is used to investigate the covariation of DC-shifts and performance in reaction time tasks, mental tasks and signal detection by varying DC-shifts systematically. The procedure was also applied to different patient groups to test the functional significance of distinct brain regions and to explore deficits in patient groups.     

Effects of tailoring ingredients in auditory persuasive health messages on fruit and vegetable intake

Objective: Health messages can be tailored by applying different tailoring ingredients, among which personalisation, feedback and adaptation. This experiment investigated the separate effects of these tailoring ingredients on behaviour in auditory health persuasion. Furthermore, the moderating effect of self-efficacy was assessed.

Design: The between-participants design consisted of four conditions. A generic health message served as a control condition; personalisation was applied using the recipient’s first name, feedback was given on the personal state, or the message was adapted to the recipient’s value.

Main outcome measures: The study consisted of a pre-test questionnaire (measuring fruit and vegetable intake and perceived difficulty of performing these behaviours, indicating self-efficacy), exposure to the auditory message and a follow-up questionnaire measuring fruit and vegetable intake two weeks after message exposure (n = 112).

Results: ANCOVAs showed no main effect of condition on either fruit or vegetable intake, but a moderation was found on vegetable intake: When self-efficacy was low, vegetable intake was higher after listening to the personalisation message. No significant differences between the conditions were found when self-efficacy was high.

Conclusion: Individuals with low self-efficacy seemed to benefit from incorporating personalisation, but only regarding vegetable consumption. This finding warrants further investigation in tailoring research.     

The cycle of violence as a function of PTSD and appetitive aggression: A longitudinal study with Burundian soldiers

During deployment, soldiers face situations in which they are not only exposed to violence but also have to perpetrate it themselves. This study investigates the role of soldiers' levels of posttraumatic stress disorder (PTSD) symptoms and appetitive aggression, that is, a lust for violence, for their engaging in violence during deployment. Furthermore, factors during deployment influencing the level of PTSD symptoms and appetitive aggression after deployment were examined for a better comprehension of the maintenance of violence. Semi-structured interviews were conducted with 468 Burundian soldiers before and after a 1-year deployment to Somalia. To predict violent acts during deployment (perideployment) as well as appetitive aggression and PTSD symptom severity after deployment (postdeployment), structural equation modeling was utilized. Results showed that the number of violent acts perideployment was predicted by the level of appetitive aggression and by the severity of PTSD hyperarousal symptoms predeployment. In addition to its association with the predeployment level, appetitive aggression postdeployment was predicted by violent acts and trauma exposure perideployment as well as positively associated with unit support. PTSD symptom severity postdeployment was predicted by the severity of PTSD avoidance symptoms predeployment and trauma exposure perideployment, and negatively associated with unit support. This prospective study reveals the importance of appetitive aggression and PTSD hyperarousal symptoms for the engagement in violent acts during deployment, while simultaneously demonstrating how these phenomena may develop in mutually reinforcing cycles in a war setting.     

Social Status and the Desire to Resort to Violence: Using the Example of Uganda's Former Child Soldiers

Committing violent acts can be appealing, fascinating, exciting, and addictive (i.e., appetitive). Cultural settings that accept violence as a means to power and success promote this appetitive form of aggression. Former child soldiers of Uganda with military rank reported committing a greater variety of violent acts compared to those without rank. They experienced aggressive behavior as more positive than both those without rank and controls who had never been involved in armed groups. The relation between the number of individually committed offense types and appetitive aggression is weaker in former child soldiers without rank compared to those with rank. This indicates that the potential for rapid development of appetitive aggression is rewarded with higher social status in war-afflicted communities.     

Control of preference in children by conditioned positive reinforcement

A preference measure was employed with children to evaluate the conditioned positive reinforcing function of a stimulus that preceded reinforcement. A match-to-sample procedure was arranged in which subjects could respond to either the form or color dimension of a compound sample stimulus. Intermittent token reinforcement was provided equally for color and form matches. Two stimuli were employed (Stimulus A and Stimulus B), each consisting of a distinctive tone and colored light. One of these stimuli (the paired stimulus) preceded each token delivery, and the other did not (nonpaired stimulus). The paired stimulus was dependent upon each response to one match dimension, and the nonpaired stimulus followed each response to the other dimension. Three of the five subjects responded primarily to the dimension that was followed by the paired stimulus. This effect was obtained regardless of which stimulus (A or B) was paired and on which match dimension (color or form) the paired stimulus was dependent. These results were unaltered by discontinuing the nonpaired stimulus. The other two subjects demonstrated consistent preferences for the form dimension and Stimulus A, respectively.     

Changes of chaoticness in spontaneous EEG/MEG

Depending on the task being investigated in EEG/MEG experiments, the corresponding signal is more or less ordered. The question still open is how can one detect the changes of this order while the tasks performed by the brain vary continuously. By applying a static measurement of the fractal dimension or Lyapunov exponent, different brain states could be characterized. However, transitions between different states may not be detected, especially if the moments of transitions are not strictly defined. Here we show how the dynamical measure based on the largest local Lyapunov exponent can be applied for the detection of the changes of the chaoticity of the brain processes measured in EEG and MEG experiments. In this article, we demonstrate an algorithm for computation of chaoticity that is especially useful for nonstationary signals. Moreover, we introduce the idea that chaoticity is able to detect, locally in time, critical jumps (phase-transition-like phenomena) in the human brain, as well as the information flow through the cortex.     

Structural and Functional Neuroplasticity in Relation to Traumatic Stress

ABSTRACT— The body's stress response is an essential adaptive and protective mechanism to cope with threatening situations. However, chronic or traumatic stress leads to structural and functional alterations in the traumatized brain. We argue for a building-block effect: Exposure to different types of traumatic events increases the probability of developing posttraumatic stress disorder (PTSD), via incremental enlargement of a fear network. We summarize evidence of brain changes in PTSD, including recent results from research on animal models of stress-related neuroplastic remodeling, with an emphasis on structural and functional changes in the hippocampus, the amygdala, and the medial prefrontal cortex.