Konstantina Zougkou

The Serotonin Transporter Gene Alters Sensitivity to Attention Bias Modification: Evidence for a Plasticity Gene

Background Attention bias modification (ABM) procedures have been shown to modify biased attention with important implications for emotional vulnerability and resilience. The use of ABM to reduce potentially toxic biases, for instance, is a newly emerging therapy for anxiety disorders. A separate line of gene-by-environment interaction research proposes that many so-called vulnerability genes or risk alleles are better seen as plasticity genes, as they seem to make individuals more susceptible to environmental influences for better and for worse. Methods A standard ABM procedure was used with a sample of 116 healthy adults. Participants were randomly assigned to one of two training groups. One received an ABM procedure designed to induce a bias in attention toward negative material, while the other was trained toward positive pictures. Individuals with low- and high-expressing forms of the serotonin transporter gene (5-HTTLPR) were compared. Results Those with a low-expression form (S/S, S/Lg, or Lg/Lg) of the 5-HTTLPR gene developed stronger biases for both negative and positive affective pictures relative to those with the high-expression (La/La) form of the gene. Conclusions Here, we report the first evidence that allelic variation in the promotor region of the 5-HTTLPR gene predicts different degrees of sensitivity to ABM. These results suggest a potential cognitive mechanism for the gene-by-environment interactions that have been found in relation to the serotonin transporter gene. Variation on this genotype may therefore determine who will benefit most (and least) from therapeutic interventions, adversity, and supportive environments.

Does short-term exposure to mobile phone base station signals increase symptoms in individuals who report sensitivity to electromagnetic fields? A double-blind randomized provocation study

Background Individuals with idiopathic environmental illness with attribution to electromagnetic fields (IEI-EMF) believe they suffer negative health effects when exposed to electromagnetic fields from everyday objects such as mobile phone base stations. Objectives This study used both open provocation and double-blind tests to determine if sensitive and control individuals experience more negative health effects when exposed to base station-like signals compared with sham. Methods Fifty-six self-reported sensitive and 120 control participants were tested in an open provocation test. Of these, 12 sensitive and 6 controls withdrew after the first session. The remainder completed a series of double-blind tests. Subjective measures of well-being and symptoms as well as physiological measures of blood volume pulse, heart rate, and skin conductance were obtained. Results During the open provocation, sensitive individuals reported lower levels of well-being in both the global system for mobile communication (GSM) and universal mobile telecommunications system (UMTS) compared with sham exposure, whereas controls reported more symptoms during the UMTS exposure. During double-blind tests the GSM signal did not have any effect on either group. Sensitive participants did report elevated levels of arousal during the UMTS condition, whereas the number or severity of symptoms experienced did not increase. Physiological measures did not differ across the three exposure conditions for either group. Conclusions Short-term exposure to a typical GSM base station-like signal did not affect well-being or physiological functions in sensitive or control individuals. Sensitive individuals reported elevated levels of arousal when exposed to a UMTS signal. Further analysis, however, indicated that this difference was likely to be due to the effect of order of exposure rather than the exposure itself.

Preconscious processing biases predict emotional reactivity to stress.

Background Anxiety vulnerability is associated with biases in attention: a tendency to selectively process negative relative to neutral or positive information. It is not clear whether this bias is: 1) related to the physiological response to stressful events, and 2) causally related to the development of anxiety disorders. Methods We tested the predictive value of both preconscious and conscious attention biases in a prospective study of stress reactivity in a nonclinical sample. One hundred four male participants were assessed at baseline and then again 4 months (n = 82) and 8 months later (n = 70). Salivary cortisol and self-report measures were obtained at the baseline testing session in addition to measures of biased attention. Subsequent emotional reactivity was assessed by means of salivary cortisol and self-reported state-anxiety responses during a laboratory-based stressor (4 months later) as well as during a real-life stressor 8 months later (i.e., examination period). Results Regression analyses indicated that a preconscious negative processing bias was the best predictor of the cortisol response to stressful events. Importantly, a measure of selective processing provided a better indicator of subsequent emotional reactivity than self-report measures of neuroticism, trait-anxiety, and extraversion. Conclusions These results suggest that preconscious biases toward negative material play a causal role in heightened anxiety vulnerability. Our results illustrate the potential utility of preconscious biases in attention in providing an early marker of anxiety vulnerability and a potential target for treatment intervention.

Short-term exposure to mobile phone base station signals does not affect cognitive functioning or physiological measures in individuals who report sensitivity to electromagnetic fields and controls.

Individuals who report sensitivity to electromagnetic fields often report cognitive impairments that they believe are due to exposure to mobile phone technology. Previous research in this area has revealed mixed results, however, with the majority of research only testing control individuals. Two studies using control and self-reported sensitive participants found inconsistent effects of mobile phone base stations on cognitive functioning. The aim of the present study was to clarify whether short-term (50 min) exposure at 10 mW/m(2) to typical Global System for Mobile Communication (GSM) and Universal Mobile Telecommunications System (UMTS) base station signals affects attention, memory, and physiological endpoints in sensitive and control participants. Data from 44 sensitive and 44 matched-control participants who performed the digit symbol substitution task (DSST), digit span task (DS), and a mental arithmetic task (MA), while being exposed to GSM, UMTS, and sham signals under double-blind conditions were analyzed. Overall, cognitive functioning was not affected by short-term exposure to either GSM or UMTS signals in the current study. Nor did exposure affect the physiological measurements of blood volume pulse (BVP), heart rate (HR), and skin conductance (SC) that were taken while participants performed the cognitive tasks.

The role of working memory in information acquisition and decision making: Lessons from the binary prediction task

The effects of memory constraints upon information acquisition and decision making were examined in two experiments using binary prediction tasks, where participants observe outcomes for two options before deciding which one to bet upon. Our studies extend previous investigations to the case where participants learn the structure of the task through observation, but where information acquisition is separated from the task of prediction. Participants with higher cognitive capacity (larger memory span or higher intelligence) were more likely to adopt the “maximizing” strategy (always selecting the more frequent alternative). This finding conflicts with some recent investigations of similar tasks, a contrast that implies that the presence of feedback on choices may be important in determining the strategic actions of high-capacity individuals. Participants selecting the optimal strategy were in turn more efficient in their data acquisition. The behaviour of participants adopting suboptimal choice strategies was consistent with prediction based upon a “narrow window of experience”—that is, seeking to match the characteristics of small samples of observations.

ERP correlates of motivating voices: quality of motivation and time-course matters

Abstract Here, we conducted the first study to explore how motivations expressed through speech are processed in real-time. Participants listened to sentences spoken in two types of well-studied motivational tones (autonomy-supportive and controlling), or a neutral tone of voice. To examine this, listeners were presented with sentences that either signaled motivations through prosody (tone of voice) and words simultaneously (e.g. ‘You absolutely have to do it my way’ spoken in a controlling tone of voice), or lacked motivationally biasing words (e.g. ‘Why don’t we meet again tomorrow’ spoken in a motivational tone of voice). Event-related brain potentials (ERPs) in response to motivations conveyed through words and prosody showed that listeners rapidly distinguished between motivations and neutral forms of communication as shown in enhanced P2 amplitudes in response to motivational when compared with neutral speech. This early detection mechanism is argued to help determine the importance of incoming information. Once assessed, motivational language is continuously monitored and thoroughly evaluated. When compared with neutral speech, listening to controlling (but not autonomy-supportive) speech led to enhanced late potential ERP mean amplitudes, suggesting that listeners are particularly attuned to controlling messages. The importance of controlling motivation for listeners is mirrored in effects observed for motivations expressed through prosody only. Here, an early rapid appraisal, as reflected in enhanced P2 amplitudes, is only found for sentences spoken in controlling (but not autonomy-supportive) prosody. Once identified as sounding pressuring, the message seems to be preferentially processed, as shown by enhanced late potential amplitudes in response to controlling prosody. Taken together, results suggest that motivational and neutral language are differentially processed; further, the data suggest that listening to cues signaling pressure and control cannot be ignored and lead to preferential, and more in-depth processing mechanisms.

You 'have' to hear this: Using tone of voice to motivate others

The present studies explored the role of prosody in motivating others, and applied self-determination theory (Ryan & Deci, 2000) to do so. Initial studies describe patterns of prosody that discriminate motivational speech. Autonomy support was expressed with lower intensity, slower speech rate and less voice energy in both motivationally laden and neutral (but motivationally primed) sentences. In a follow-up study, participants were able to recognize motivational prosody in semantically neutral sentences, suggesting prosody alone may carry motivational content. Findings from subsequent studies also showed that an autonomy-supportive as compared with a controlling tone facilitated positive personal (perceived choice and lower perceived pressure, well-being) and interpersonal (closeness to others and prosocial behaviors) outcomes commonly linked to this type of motivation. Results inform both the social psychology (in particular motivation) and psycho-linguistic (in particular prosody) literatures and offer a first description of how motivational tone alone can shape listeners’ experiences.

The processing of number scales beyond whole numbers in development: Dissociations in arithmetic in Turner’s syndrome

ABSTRACT The arithmetical skills in two children with Turner’s syndrome (TS), each the focus of a case study, were analysed in whole numbers and other number scales that have not been systematically explored previously, fractions, decimals, percentages, and negative numbers. The intention was to identify the fractionation of arithmetical skills. The two girls with TS showed dissociations of arithmetical skill in the calculation system of whole numbers that support its modular organization. Fractionation of skills was observed in some components of the other number scales, suggesting an analogous organization within these scales. The operational specificity of impairment within number scales but not others argued against a unitary arithmetical system but rather for autonomous operational scales within distinct number scales. A general model of arithmetic is proposed.