Applied Psychophysiology and Biofeedback

This pilot study evaluated the effect of computer animated relaxation therapy in children between 7 and 13 years with tension-type headache and the children's experiences with the therapy. The therapy consisted of an uncontrolled nine-session course in modified progressive relaxation therapy assisted by computer animated surface EMG provided from the trapezius muscles and with the physiotherapist as a participant observer. Outcome measures were (a) headache frequency and intensity, (b) pericranial tenderness, (c) tension patterns, and (d) evaluations assessed at baseline and at 3 months follow up. Nine children, mean age 10.9 (SD 1.7) years, diagnosed with frequent episodic or chronic tension-type headache completed the course. The results showed a mean improvement of 45% for headache frequency at 3 months follow up versus baseline and a significant reduction in headache frequency for all participants and in Total Tenderness Score for children with frequent episodic tension-type headache. The children expressed a growing understanding of body reactions and an acquired ability to deactivate and regulate these reactions. Computer animated SEMG seems an applicable learning strategy for young headache sufferers. This study suggests that children below the age of 13 need both the dialog and guidance from a participant observer in order to achieve body awareness.

Psychophysiological assessments measuring heart rate, systolic and diastolic blood pressure, and skin resistance level were conducted on 7 male compulsive gamblers and on 7 age and gender matched controls while both groups performed mental arithmetic and listened to individualized tapes of the gamblers' preferred form of gambling and an individualized fear tape. Heart rate responses of the gamblers to the 2 gambling audiotapes were significantly greater than those found for the controls whereas the groups did not differ on mental arithmetic or the fear provoking scene, confirming some degree of cue-specific arousal in gamblers. The other physical responses did not yield such strong results. If physiological arousal provides the motivational basis for gambling and is maintained on an intermittent schedule of reinforcement, the findings may have implications for the treatment of compulsive gambling.

19-Channel Z-Score Neurofeedback (19ZNF) is a modality using 19-electrodes with real-time normative database z-scores, suggesting effective clinical outcomes in fewer sessions than traditional neurofeedback. Thus, monitoring treatment progression and clinical outcome is necessary. The area of focus in this study was a methodology of quantitative analysis for monitoring treatment progression and clinical outcome with 19ZNF. This methodology is noted as the Sites-of-Interest, which included repeated measures analyses of variance (rANOVA) and t-tests for z-scores; it was conducted on 10 cases in a single subject design. To avoid selection bias, the 10 sample cases were randomly selected from a pool of 17 cases that met the inclusion criteria. Available client outcome measures (including self-report) are briefly discussed. The results showed 90 % of the pre-post comparisons moved in the targeted direction (z = 0) and of those, 96 % (80 % Bonferroni corrected) of the t-tests and 96 % (91 % Bonferroni corrected) of the rANOVAs were statistically significant; thus indicating a progression towards the mean in 15 or fewer 19ZNF sessions. All cases showed and reported improvement in all outcome measures (including quantitative electroencephalography assessment) at case termination.

Although stress is defined as a perceived threat, the implications of stress go well beyond physical well-being. In the words of Carl Jung, "Every crisis is a spiritual crisis." Western science, so strongly influenced by the Cartesian Principle of Reductionism, has ignored the essence and significance of human spirituality in the health and healing process. Holistic healing honors the integration, balance, and harmony of mind, body, spirit, and emotions, where the whole is greater than the sum of the parts. Stress (unresolved issues of anger and fear) chokes the human spirit, the life force of human energy, which ultimately affects the physical body. From the perspectives of both physics and metaphysics, stress is a disruption in the state of coherence between the layers of consciousness in the human energy field. The emerging paradigm of health reunites mind, body, and spirit, and considers health as a function of coherence among the energy levels of these components.

In their commentary on EEG Biofeedback for Autism Spectrum Disorders (Kouijzer et al. 2013) Coben and Ricca (2014) offer explanations for the apparent lack of improvement following electroencephalography (EEG) biofeedback-training as compared to skin conductance (SC) biofeedback-training. The authors suggest that a different EEG-biofeedback regime using a bipolar montage directed at coherence might have been more successful. We have identified three issues in Coben and Ricca’s commentary that we think are important to discuss in the current reply.First, we disagree with the authors’ qualification that our study revealed no effects of EEG-biofeedback training. An important finding in our study was the improvement in the Trail Making Test in participants who succeeded to down regulate theta activation trough EEG-biofeedback. No such effect was found for the SC biofeedback group or in the group of participants who were not successful in down regulating theta power over time. In a study in ...

Two different groups of normal college students were formed: One (the alpha group) received 10-Hz audiovisual (AV) stimulation for 8 minutes, and the other (beta) group received 22-Hz AV stimulation for 8 minutes. EEG power in the alpha (8-13 Hz) and beta (13-30 Hz) bands was FFT-extracted before, during, and for 24 minutes after stimulation. It was found that baseline (prestimulation) alpha and beta power predict the effects of stimulation, leading to individual differences in responsivity. High-baseline alpha participants showed either no entrainment or relatively prolonged entrainment with alpha stimulation. Low-baseline participants showed transient entrainment. Baseline alpha also predicted the direction of change in alpha with beta stimulation. Baseline beta and alpha predicted beta band response to beta stimulation, which was transient enhancement in some participants, inhibition in others. Some participants showed relatively prolonged beta enhancement with beta stimulation.

Functional abdominal pain (FAP) causes disruption of daily activities/missed school days, over utilization of healthcare, unnecessary surgeries, and anxiety in 10-15% of children. Its etiology is not clearly understood, however the success of several clinical protocols suggests that autonomic dysregulation is a factor. In this study autonomic activity, including heart rate variability (HRV), was compared between children with FAP and a comparison group. Twenty children with FAP and 10 children without FAP between the ages of 5 and 17 years old were compared on autonomic regulation using an ambulatory system at baseline and 8 weeks later. Children with FAP participated in 6 sessions of HRV biofeedback aimed at normalizing autonomic balance. At baseline, children with FAP appear to have more autonomic dysregulation than children without FAP. After completing HRV biofeedback, the FAP group was able to significantly reduce their symptoms in relation to significantly increasing their autonomic balance. In a sample of children with FAP, it appears that HRV biofeedback treatment improved their symptoms and that a change in vagal tone was a potential mediator for this improvement. The present study appears to point to excessive vagal withdrawal as an underlying mechanism of FAP.

Recurrent abdominal pain (RAP) is a significant and common problem among pediatric populations. Based on results from randomized controlled trials there are no established efficacious treatments for this disorder. Biofeedback (BFB) and other psychological treatments offer logically appealing alternatives or adjuncts to medical interventions and there is some evidence to support their use. This paper presents a typical case of RAP that exemplifies how the lack of integration of the biopsychosocial model may result in less than optimal treatment. Specifically, it demonstrates that the patient was exposed to potentially risky treatments that lack evidence to support their use and were not beneficial. Although there was evidence of psychological involvement early in the treatment, this was only attended to following numerous medical trials and exploratory surgery over three years. The patient was finally referred for BFB and during a course of seven sessions over five months that variously included heart rate variability and skin temperature feedback along with extensive home practice of paced breathing and hand warming the patient achieved significant symptom reduction and improved coping abilities. This case vividly illustrates the need for multidisciplinary collaboration and full implementation and integration of the biopsychosocial model of health and illness.

To better understand visual processing abnormalities in autism we studied the attention orienting related frontal event potentials (ERP) and the sustained attention related centro-parietal ERPs in a three stimulus oddball experiment. The three stimulus oddball paradigm was aimed to test the hypothesis that individuals with autism abnormally orient their attention to novel distracters as compared to controls. A dense-array 128 channel EGI electroencephalographic (EEG) system was used on 11 high-functioning children and young adults with autism spectrum disorder (ASD) and 11 age-matched, typically developing control subjects. Patients with ASD showed slower reaction times but did not differ in response accuracy. At the anterior (frontal) topography the ASD group showed significantly higher amplitudes and longer latencies of early ERP components (e.g., P100, N100) to novel distracter stimuli in both hemispheres. The ASD group also showed prolonged latencies of late ERP components (e.g., P2a, N200, P3a) to novel distracter stimuli in both hemispheres. However, differences were more profound in the right hemisphere for both early and late ERP components. Our results indicate augmented and prolonged early frontal potentials and a delayed P3a component to novel stimuli, which suggest low selectivity in pre-processing and later-stage under-activation of integrative regions in the prefrontal cortices. Also, at the posterior (centro-parietal) topography the ASD group showed significantly prolonged N100 latencies and reduced amplitudes of the N2b component to target stimuli. In addition, the latency of the P3b component was prolonged to novel distracters in the ASD group. In general, the autistic group showed prolonged latencies to novel stimuli especially in the right hemisphere. These results suggest that individuals with autism over-process information needed for the successful differentiation of target and novel stimuli. We propose the potential application of ERP evaluations in a novelty task as outcome measurements in the biobehavioral treatment (e.g., EEG biofeedback, TMS) of autism.

Recurrent and frightening dreams are commonly experienced by patients who suffer from post-traumatic stress disorder after a motor vehicle accident. Such nocturnal episodes, if left untreated, can result in the experience of severe distress with physical, emotional, and psychophysiological concomitant. The present single-case study investigated the effects of the standard autogenic exercises and autogenic abreaction in reducing the frequency and severity of post-traumatic nightmares in a survivor of a car crash. The patient was also instructed in two additional organ-specific formulas in order to improve her sleep. The results of the study showed that the interventions were successful in effectively treating the patient's distressing nightmares. Follow-up data suggested that the treatment effects persisted after the termination of therapy. Suggestions for future investigations are discussed.

We investigated the potential impact of abuse history on autonomic regulation and psychological wellbeing in a sample of women who reported a history of abuse without Post Traumatic Stress Disorder. To measure autonomic regulation, heart rate data was collected before and after the participant rode a stationary bike for one mile. We found that abuse history was associated with less vagal regulation of the heart (i.e., respiratory sinus arrhythmia) and an inability to rapidly re-engage vagal regulation immediately following mild exercise to support a calm physiological state. These findings are consistent with clinical impressions that abused individuals may have a lower threshold to express fight/flight behaviors in response to stress and have difficulty shifting from mobilization to calmness. We also found that abuse history was related to psychological wellbeing. Women with an abuse history reported a greater use of dysfunctional coping methods and lower self-concept. Further, analyses indicated that there was a cumulative effect, whereby women who reported more recent abuse reported using more dysfunctional coping methods, having more mood disturbance, and lower self-concept. The findings underscore the importance of evaluating both the psychological and physiological effects of trauma, even in the absence of a diagnosis of PTSD.

Global self-esteem was tested to predict quicker cardiovascular adaptation during stressful oral thesis presentation and faster habituation from the first to the second and third thesis presentations. Nineteen graduate students initially rated their global self-esteem and afterwards orally presented their theses proposals in 20-min presentations to their thesis supervisor and peers. A second and third presentation of the revised thesis concepts took place at 4-weeks intervals. Ambulatory blood pressure and heart rate were assessed repeatedly during the presentations. Post-talk self ratings of stressfulness indicated presentations to be a strong public speaking stressor. One hundred and thirty-eight measurements of systolic (SBP), diastolic blood pressure (DBP), and heart rate (HR) showed a significant adaptation (decrease) during presentations. There was an overall mean level decrease from the first to the second, and the second to the third presentations in HR, but not in SBP and DBP. However, habituation in SBP and DBP across three presentations was significantly faster (p < .05) in those participants who initially reported higher levels of global self-esteem. Higher global self-esteem did not foster adaptation within the presentations. Self-esteem is discussed as an important individual resource that allows successful coping with recurring evaluative threats.

Twenty-one children and adolescents (age range 8-17, mean 12.7 years) who had been in motor vehicle accidents (MVAs), and 14 non-MVA controls matched for age and gender, underwent a psychophysiological assessment in which heart rate, systolic and diastolic blood pressure, and skin conductance were measured during baseline and two stressor phases: mental arithmetic and listening to and imagining a MVA like their own. The eight youth who currently met criteria for PTSD or sub-syndromal PTSD significantly reported more subjective distress to the MVA audiotape than the 13 MVA non-PTSD youth or the 14 non-MVA controls. All groups responded physiologically to the mental arithmetic. However, in contrast to expectations, there were no differential physiological responses among the groups to the stimuli reminiscent of the trauma. Possible explanations are explored.

The aim of the present study was to investigate startle responses in motor vehicle accident (MVA) survivors to trauma-related, startle, and neutral sounds. Participants were 17 MVA survivors, 11 of whom participated in a controlled treatment study comparing cognitive-behavioral treatment (CBT) and supportive therapy (ST) versus a waitlist condition. Though participants differed significantly in their pretreatment clinical status and symptom severity, these differences were not reflected by group differences in EMG (at orbicularis oculi) to the stimuli at the initial assessment. Some cue-specificity was found, as all participants showed larger startle responses to trauma-related sounds, compared to startle and neutral sounds. At posttreatment, a significant reduction in EMG reactivity to all stimuli was observed in participants who received active treatment (either CBT or ST), compared to waitlist controls. The use of startle responses as a PTSD treatment outcome index is discussed.

In the first of two experiments, we compared the accuracy of the P300 concealed information test protocol as a function of numbers of trials experienced by subjects and ERP averages analyzed by investigators. Contrary to Farwell et al. (Cogn Neurodyn 6(2):115-154, 2012), we found no evidence that 100 trial based averages are more accurate than 66 or 33 trial based averages (all numbers led to accuracies of 84-94 %). There was actually a trend favoring the lowest trial numbers. The second study compared numbers of irrelevant stimuli recalled and recognized in the 3-stimulus protocol versus the complex trial protocol (Rosenfeld in Memory detection: theory and application of the concealed information test, Cambridge University Press, New York, pp 63-89, 2011). Again, in contrast to expectations from Farwell et al. (Cogn Neurodyn 6(2):115-154, 2012), there were no differences between protocols, although there were more irrelevant stimuli recognized than recalled, and irrelevant 4-digit number group stimuli were neither recalled nor recognized as well as irrelevant city name stimuli. We therefore conclude that stimulus processing in the P300-based complex trial protocol-with no more than 33 sweep averages-is adequate to allow accurate detection of concealed information.

StressEraser is a commercially marketed biofeedback device designed to enhance heart rate variability. StressEraser makes its internal calculations on beat-to-beat measures of finger pulse intervals. However, the accuracy and precision of StressEraser in quantifying interbeat intervals using finger pulse intervals has not been evaluated against standard laboratory equipment using R-R intervals. Accuracy was assessed by simultaneously recording interbeat intervals using StressEraser and a standard laboratory ECG system. The interbeat intervals were highly correlated between the systems. The average deviation in interbeat interval recordings between the systems was approximately 6 ms. Moreover, correlations approached unity between the systems on estimates of heart period, heart rate, and heart rate variability. Feedback from StressEraser is based on an interbeat time series that provides sufficient information to provide an excellent estimate of the dynamic changes in heart rate and heart rate variability. The slight variations between StressEraser and the laboratory equipment in quantifying heart rate and heart rate variability are due to features related to monitoring heart rate with finger pulse: (1) a lack in precision in the peak of the finger pulse relative to the clearly defined inflection point in the R-wave, and (2) contribution of variations in pulse transit time.

In this study we evaluated the efficacy of visual rehabilitation by means of two different types of biofeedback techniques in patients with age related macular degeneration (AMD). Thirty patients, bilaterally affected by AMD, were randomly divided in two groups: one group was treated with an acoustic biofeedback (AB group), the other was treated with luminous biofeedback of a black and white checkerboard flickering during the examination (LB group). All patients underwent a complete ophthalmological examination. Rehabilitation consisted of 12 training sessions of 10 min for each eye performed once a week for both groups. Both groups showed better visual performance after rehabilitation and luminous flickering biofeedback stimulus showed a statistically significant improvement in training the patients to modify their preferred retinal locus in comparison to acoustic biofeedback. This suggests that it might be possible in the damaged retina to override dead photoreceptor and outer retinal layers and involve residual surviving cells, as well as amplify and integrate retinal and brain cortex plasticity by using other spared channels towards associative pathways.

The Raynaud's Treatment Study (RTS) compared temperature biofeedback training and a behavioral control procedure (frontalis EMG biofeedback) with nifedipine-XL and a medication placebo for treatment of primary Raynaud's phenomenon (RP) in a large (N = 313) multicenter trial. The present study describes the RTS biofeedback protocols and presents data on the acquisition of digital skin temperature and frontalis EMG responses in the RTS. The findings point to substantial problems with acquisition of physiological self-regulation skills in the RTS. Only 34.6% of the Temperature Biofeedback group (N = 81) and 55.4% of the EMG Biofeedback group (N = 74) successfully learned the desired physiological response. In contrast, 67.4% of a Normal Temperature Biofeedback group (N = 46) learned hand warming. Multivariate analysis found that coping strategies, anxiety, gender, and clinic site predicted acquisition of hand-warming skills whereas variables related to RP disease severity did not. Physiological data showed vasoconstriction in response to the onset of biofeedback and also found that performance in the initial sessions was critical for successful acquisition. These findings indicate that attention to the emotional and cognitive aspects of biofeedback training, and a degree of success in the initial biofeedback sessions, are important for acquisition.

Biofeedback was used to increase forearm-muscle tension. Feedback was delivered under continuous reinforcement (CRF), variable interval (VI), fixed interval (FI), variable ratio (VR), and fixed ratio (FR) schedules of reinforcement when college students increased their muscle tension (electromyograph, EMG) above a high threshold. There were three daily sessions of feedback, and Session 3 was immediately followed by a session without feedback (extinction). The CRF schedule resulted in the highest EMG, closely followed by the FR and VR schedules, and the lowest EMG scores were produced by the FI and VI schedules. Similarly, the CRF schedule resulted in the greatest amount of time-above-threshold and the VI and FI schedules produced the lowest time-above-threshold. The highest response rates were generated by the FR schedule, followed by the VR schedule. The CRF schedule produced relatively low response rates, comparable to the rates under the VI and FI schedules. Some of the data are consistent with the partial-reinforcement-extinction effect. The present data suggest that different schedules of feedback should be considered in muscle-strengthening-contexts such as during the rehabilitation of muscles following brain damage or peripheral nervous-system injury.

When analyzed separately, data from small studies provide only limited information with limited clinical generalizability, due to small sample size, differing assessments, and limited scope. In this methodological paper we outline a theoretical framework for performing meta-analysis of data obtained from disparate studies using disparate tests, based on calibration of the data from such studies and tests into a unified probability scale. We apply this method to combine the data from five studies examining the diagnostic abilities of different assessments of Attention Deficit/Hyperactivity Disorder (ADHD), including behavioral rating scales and EEG assessments. The studies enrolled a total of 111 subjects, 56 ADHD and 55 controls. Each individual study had a small sample focused on a specific age/gender group, for example 8 boys ages 6–10, and generally had insufficient power to detect statistically significant differences. No gender, or age comparisons were possible within any single study. However, when calibrated and combined, the data resulted in a clear separation between ADHD versus non-ADHD groups in males below the age of 16 (p < 0.001), males above the age of 16, (p = 0.015), females below the age of 16, (p = 0.0014), and females above the age of 16, (p = 0.0022). We conclude that if data from various studies using various tests are made comparable, the resulting combined sample size and the increased diversity of the combined sample lead to increased significance of the statistical tests and allow for cross-sectional comparisons, which are not possible within each individual study.

The main purposes of the present study were to substantiate the existence of the four types of performance categories (i.e., optimal-automatic, optimal-controlled, suboptimal-controlled, and suboptimal-automatic) as hypothesised in the multi-action plan (MAP) model, and to investigate whether some specific affective, behavioural, psychophysiological, and postural trends may typify each type of performance. A 20-year-old athlete of the Italian shooting team, and a 46-year-old athlete of the Italian dart-throwing team participated in the study. Athletes were asked to identify the core components of the action and then to execute a large number of shots/flights. A 2 × 2 (optimal/suboptimal × automated/controlled) within subjects multivariate analysis of variance was performed to test the differences among the four types of performance. Findings provided preliminary evidence of psychophysiological and postural differences among four performance categories as conceptualized within the MAP model. Monitoring the entire spectrum of psychophysiological and behavioural features related to the different types of performance is important to develop and implement biofeedback and neurofeedback techniques aimed at helping athletes to identify individual zones of optimal functioning and to enhance their performance.

Motor imagery (MI) is the mental representation of an action without any concomitant movement. MI has been used frequently after peripheral injuries to decrease pain and facilitate rehabilitation. However, little is known about the effects of MI on muscle activation underlying the motor recovery. This study aimed to assess the therapeutic effects of MI on the activation of lower limb muscles, as well as on the time course of functional recovery and pain after surgery of the anterior cruciate ligament (ACL). Twelve patients with a torn ACL were randomly assigned to a MI or control group, who both received a series of physiotherapy. Electromyographic activity of the quadriceps, pain, anthropometrical data, and lower limb motor ability were measured throughout a 12-session therapy. The data provided evidence that MI elicited greater muscle activation, even though imagery practice did not result in pain decrease. Muscle activation increase might originate from a redistribution of the central neuronal activity, as there was no anthropometric change in lower limb muscles after imagery practice. This study confirmed the effectiveness of integrating MI in a rehabilitation process by facilitating muscular properties recovery following motor impairment. MI may thus be considered a reliable adjunct therapy to help injured patients to recover motor functions after reconstructive surgery of ACL.

Electroencephalography (EEG) has been extensively used in studies of the frontal asymmetry of emotion and motivation. This study investigated the midfrontal EEG activation, heart rate and skin conductance during an emotional face analog of the Stroop task, in anxious and non-anxious participants. In this task, the participants were asked to identify the expression of calm, fearful and happy faces that had either a congruent or incongruent emotion name written across them. Anxious participants displayed a cognitive bias characterized by facilitated attentional engagement with fearful faces. Fearful face trials induced greater relative right frontal activation, whereas happy face trials induced greater relative left frontal activation. Moreover, anxiety specifically modulated the magnitude of the right frontal activation to fearful faces, which also correlated with the cognitive bias. Therefore, these results show that frontal EEG activation asymmetry reflects the bias toward facilitated processing of fearful faces in anxiety.

J. A. Gray's (1975) theory distinguishes between two motivational systems, which he refers to as the behavioral activation system (BAS) and the behavioral inhibition system (BIS). D. C. Fowles (1980) has shown that heart rate responses reflect activity of the BAS, and electrodermal responses reflect activity of the BIS. Both BAS and BIS are reliably activated during in-vivo exposure to fearful situations (F. H. Wilhelm & W. T. Roth, 1998). However, due to the constraints imposed by virtual reality (VR), we hypothesized that VR exposure to fearful situations would activate the BIS alone. To test this hypothesis, a VR free-standing elevator simulation was presented to participants selected for high and low fear of heights. As predicted, the high-anxious group strongly responded electrodermally (effect size d = 1.53), but showed only minimal HR elevations during exposure (d = 0.12), and little other cardiovascular or respiratory changes. The low-anxious control group showed little electrodermal and HR reactivity (d = 0.28 and 0.12). A comparison with data from a previous study demonstrated that this pattern was in stark contrast to the large electrodermal and cardiovascular response observed during situational in-vivo exposure outside the laboratory. We conclude that the BIS, but not BAS, is selectively activated during VR exposure, causing discordance between self-report and commonly used physiological measures of anxiety. Results are discussed within the framework of E. B. Foa & M. J. Kozak's (1986) emotional processing theory of fear modification, suggesting different mechanisms underlying VR and in-vivo exposure treatments.

The purpose of this study was to determine whether (1) there is a menstrual phase effect on blood pressure (BP) and heart rate (HR), and (2) the effects of physical effort, posture, or moods on BP and HR is mediated by the menstrual phase. Twelve normotensive women, aged between 28 and 50, with normal menstrual cycles were studied. BP was measured at 30- to 60-min intervals during a 24-hr period using an ambulatory BP monitor on Days 1, 8, 15, and 22 of the menstrual cycle. Participants were asked to report their posture, physical effort, and mood ("annoyed," "tense," and "happy") on 5-point Likert-type scales each time the ambulatory BP monitor took measurements. Systolic BP (SBP) was lower on Day 8 of the cycle. Diastolic BP (DBP) and HR were lower on Days 1 and 8. Daytime SBP was affected by the time of the day and posture, but not by moods, whereas daytime DBP was affected by posture and levels of tenseness. The level of physical effort only affected HR, not BP. The average daytime physical and emotional variables had little influence over the average daytime BP. In 12 normotensive women with a normal menstrual cycle, SBP was lower during the follicular phase and DBP and HR were lower during the follicular phase and menstruation even after controlling the effects of other factors. Physical activity or moods had only momentary effects on BP or HR. A cross-validation statistical method used is suggested to study how individuals are affected by various factors. With the use of this method, the inclusion of menstrual phase in the model improved the prediction of SBP for 5 out of the 12 women studied.

The aim of this study was to compare actual versus mentally simulated preparation for a complex motor skill. Two behavioral periods are observed during weightlifting: (i) an initial phase in which the subject standing behind the bar is thought to focus his attention on forthcoming execution and (ii) a second phase between hands/bar contact and execution during which the subject is thought to increase activation. Such mental processes accompanying behavioral sequences are correlated with autonomic nervous system activity, phasic responses corresponding to allocation of attentional resources, and tonic variations related to increasing general activation. To study mental processes during preparation for action, 12 subjects performed actual and imagined preparation phases of execution. Six autonomic variables were measured continuously. Skin potential (chi2 = 0.16), skin temperature amplitude (Z = -0.66) and duration (Z = -1.78), skin blood flow amplitude (Z = -0.56) and duration (Z = -1.51), respiratory frequency amplitude (Z = -0.14) and duration (Z = -0.13), and duration of heart rate response (Z = -1.25) were shown to be comparable (p > .05), whatever the modality of preparation. However, during mentally simulated preparation, skin resistance response was shorter than in actual preparation (Z = -2.12, p < .05), thus attesting to a weaker load, whereas lower decrease in heart rate was elicited (Z = -1.96, p < .05). This may be explained by this particular experimental condition because mental preparation would not lead to actual action. Such autonomic variables could be used as feedback to improve performance.

Dear Professor Andrasik, I enjoyed reading a recent article by Turner et al. (2013) in your journal. The article was a comparison between the acupoint-skin resistance of patients with Rheumatoid Arthritis (RA) and that of healthy counterparts in which the skin resistance was found higher in the RA group; the authors concluded that the measurement of skin resistance at the acupoints can differentiate between the pain (RA) and the non-pain (healthy) groups. But, I would like to express my opinions on their interpretations.

The concepts of meridians and acupoints are critical to traditional Chinese medicine but are met with skepticism in Western medicine. Empirical validation of these concepts is in its beginning stages and still hampered by problems with measurement. A promising avenue and foundation for validity testing is the demonstration that acupoint activity can be reliably measured via determination of electrical resistance at well-defined body surface points. In this article, efforts are described to maximize measurement reliability; we tested a variety of protocols to determine which method of data aggregation is associated with maximal reliability. Twenty-one healthy individuals were subjected to 5 repeated measurement cycles to test the predicted increase in reliability with increasing number of aggregated measurements. Reliability, defined as internal consistency, was indeed highest for 5 measurements (mean alpha = .88). Even the aggregate of only three measures was quite reliable (alpha = .84). Reliability for measuring acupoints on the left side of the body was roughly .05 higher than on the right side. Consistent with previous literature, we conclude that with repeated measures the reliability of electrical resistance measurements at acupoints is high and that a strong foundation for validation research is now laid.

This study evaluated whether electrodermal resistance at acupuncture points (AP) systematically varies as a function of pain. The study was conceived as a proof-of-principle study in support of research on acupuncture and other complementary medicine approaches. Specifically, this study investigates whether or not electrodermal activity systematically differentiates arthritis patients with current pain from pain-free controls. Participants with rheumatoid arthritis (n = 32) and a typical pain level of at least 3 (on a 0-10 scale) were compared with case controls (n = 28) who had no medical diagnosis and were pain free. Electrodermal resistance at AP was measured with a commercial ohmmeter and compared to heart rate, blood pressure, and ratings on the Pain Catastrophization Scale and the McGill Melzack Pain Questionnaire. There were consistent differences between the experimental group and the control group on all markers of pain. Similarly, there were significant group differences and some trends for electrodermal activity at the AP labeled 'bladder,' 'gall bladder,' and 'small intestine.' It is concluded that the concept of electrodermal resistance at AP possesses criterion validity for distinguishing pain from a no pain state. This research provides support for the usefulness of measuring electrodermal activity when testing energy-based models of disease, and can be seen as a bridge between Western and Chinese medicine.

Since there are several popular beliefs about putative health benefits of amusement which are empirically substantiated poorly about putative health benefits of amusement, the immediate cardiovascular effects of amusement were studied in detail. Cardiovascular activity was studied while participants were viewing humorous films, relative to a control condition involving no amusement. High-resolution measures of heart rate, heart rate variability, continuous blood pressure, and respiration were recorded, and the phase synchronization among the variables was analyzed, which provides information on the coordinated behavior of response systems. Viewing humorous films had cardiovascular effects indicating heightened sympathetic arousal, if they elicited intense amusement. No effects were observed for variables indicating parasympathetic input to the heart. The observed effects associated with amusement were not driven by changes in the respiration. The suppression of positive affect expressions did not produce any additional activation. The transient cardiovascular effects of amusement do not correspond to beneficial correlates of a habitual positive affect disposition reported in the literature, demonstrating that it would be erroneous to argue from the long-term effects of a positive affect disposition to the effects of a single amusing event.

The purpose of this study was to examine the relationship of physical activity and cognitive function (as determined by reaction time and the trail-making test) in active versus non-active participants. Participants were divided into one of four groups: active experimental, active control, non-active experimental and non-active control. All groups completed a complex cognitive task (the trail-making test) as well as a set of reaction time tasks both before and after the experimental session. The experimental groups completed a 30-min exercise session while the control groups monitored the physical activity of the experimental group. In addition to the measures of cognitive function, heart rate variability was recorded during the pre- and post-tests. There was significant cognitive performance improvement in tasks with a higher cognitive and perceptual component. Heart rate variability data indicated that a moderate level of arousal based on sympathetic nervous system activity post exercise was associated with an increase in cognitive performance. The findings are discussed in light of the inverted-U hypothesis.

Cortisol induces attentional bias toward a negative stimulus and impaired attentional function. Depressed individuals have high levels of cortisol, and exhibit an attentional bias toward a depression-related stimulus and impaired processing speed and executive attention, which are components of attentional function. Therefore, the study tested the hypotheses that an acute increase in cortisol in response to a stressor is associated with attentional bias toward a depression-related stimulus and impaired processing speed and executive attention. Thirty-six participants were administered the dot-probe task for the measurement of attentional bias toward a depression-related stimulus and the Trail Making Test A and B for the measurement of processing speed and executive attention before and after a mental arithmetic task. It was revealed that attentional bias toward a depression-related stimulus following the stressor was observed only among the responders (i.e., participants with cortisol elevation in response to a stressor). On the other hand, no differences in the performance of processing speed and executive attention were noted between the responders and non-responders. The results indicate that acutely elevated cortisol is related to attentional bias, but is not related to processing speed and executive attention. The results have an implication for the etiology of depression.

The paper examines major criticisms of AD/HD (Attention Deficit/Hyperactivity Disorder) neurofeedback research using T. R. Rossiter and T. J. La Vaque (1995) as an exemplar and discusses relevant aspects of research methodology. J. Lohr, S. Meunier, L. Parker, and J. P. Kline (2001), D. A. Waschbusch and G. P. Hill (2001), and J. P. Kline, C. N. Brann, and B. R. Loney (2002) criticized Rossiter and La Vaque for (1) using an active treatment control; (2) nonrandom assignment of patients; (3) provision of collateral treatments; (4) using nonstandardized and invalid assessment instruments; (5) providing artifact contaminated EEG feedback; and (6) conducting multiple non-alpha protected t tests. The criticisms, except those related to statistical analysis, are invalid or are not supported as presented by the authors. They are based on the critics' unsubstantiated opinions; require redefining Rossiter and La Vaque as an efficacy rather than an effectiveness study; or reflect a lack of familiarity with the research literature. However, there are broader issues to be considered. Specifically, what research methodology is appropriate for studies evaluating the effectiveness of neurofeedback and who should make that determination? The uncritical acceptance and implementation of models developed for psychotherapy, pharmacology, or medical research is premature and ill-advised. Neurofeedback researchers should develop models that are appropriate to the technology, treatment paradigms, and goals of neurofeedback outcome studies. They need to explain the rationale for their research methodology and defend their choices.

Difficulty sleeping is a common problem with laboratory polysomnograms. This affects both polysomnograms that are used as a clinical tool to investigate sleep pathology or as an outcome variable in research. The goal of this study was to use a handheld biofeedback device (StressEraser) to improve sleep quality in the laboratory. Ten subjects without a history of sleep disorders were randomly assigned to either a StressEraser or no-treatment control condition. A sleep disturbance scale derived from sleep efficiency, REM latency, minutes of stage 1 sleep, and wake after sleep onset was created to evaluate the differences between these groups. Subjects in the StressEraser group had significantly lower scores on the sleep disturbance scale compared to the no-treatment control group (p = 0.003). Sleep latency was not improved. In conclusion, the StressEraser significantly improved sleep quality compared to a no-treatment control group. This suggests that the StressEraser may be an effective tool to help reduce the first-night effect in nighttime laboratory sleep studies.

Three experiments were conducted to evaluate the performance of a psychophysiologically controlled adaptive automation system. Subjects were asked to perform a compensatory tracking task while their electroencephalogram (EEG) was recorded and an engagement index was derived from the EEG, using the alpha, beta, and theta bandwidths: beta/(alpha + theta) and beta/theta. In Experiment I, EEG was recorded from three different sites: frontal, parietal, and temporal. Although tracking performance did not differ as a function of site, the number of task mode allocations was greater under a negative feedback contingency than under a positive feedback contingency. This effect was seen primarily from frontal sites. Experiments II and III evaluated the adaptive automation system, using extended runs under positive and negative feedback with either a slope (Experiment II) or absolute (Experiment III) criterion used to drive the system. Using either criterion, performance was found to be significantly better under negative feedback. Future evaluation and use of psychophysiologically controlled adaptive automation systems are discussed.

A review of records was carried out to examine the results obtained when people with Attention Deficit Disorder (ADD) received 40 sessions of training that combined neurofeedback with the teaching of metacognitive strategies. While not a controlled scientific study, the results, including pre- and post-measures, are consistent with previously published research concerning the use of neurofeedback with children. A significant addition is that a description of procedures is included. The 111 subjects, 98 children (age 5 to 17) and 13 adults (ages 18 to 63), attended forty 50-min sessions, usually twice a week. Feedback was contingent on decreasing slow wave activity (usually 4-7 Hz, occasionally 9-11 Hz) and increasing fast wave activity (15-18 Hz for most subjects but initially 13-15 Hz for subjects with impulsivity and hyperactivity). Metacognitive strategies related to academic tasks were taught when the feedback indicated the client was focused. Some clients also received temperature and/or EDR biofeedback during some sessions. Initially, 30 percent of the children were taking stimulant medications (Ritalin), whereas 6 percent were on stimulant medications after 40 sessions. All charts were included where pre- and post-testing results were available for one or more of the following: the Test of Variables of Attention (TOVA, n = 76), Wechsler Intelligence Scales (WISC-R, WISC-III, or WAIS-R, n = 68), Wide Range Achievement Test (WRAT 3, n = 99), and the electroencephalogram assessment (QEEG) providing a ratio of theta (4-8 Hz) to beta (16-20 Hz) activity (n = 66). Significant improvements (p < .001) were found in ADD symptoms (inattention, impulsivity, and variability of response times on the TOVA), in both the ACID pattern and the full-scale scores of the Wechsler Intelligence Scales, and in academic performance on the WRAT 3. The average gain for the full scale IQ equivalent scores was 12 points. A decrease in the EEG ratio of theta/beta was also observed. These data are important because they provide an extension of results from earlier studies (Lubar, Swartwood, Swartwood, & O'Donnell, 1995; Linden, Habib, & Radojevic, 1996). They also demonstrate that systematic data collection in a private educational setting produces helpful information that can be used to monitor students' progress and improve programs. Because this clinical work is not a controlled scientific study, the efficacious treatment components cannot be determined. Nevertheless, the positive outcomes of decreased ADD symptoms plus improved academic and intellectual functioning suggest that the use of neurofeedback plus training in metacognitive strategies is a useful combined intervention for students with ADD. Further controlled research is warranted.

This study investigated neurophysiological differences between recovering substance abusers (RSA) and controls while electroencephalogram (EEG) was continuously recorded during completion of a new assessment instrument. The participants consisted of 56 total subjects; 28 RSA and 28 non-clinical controls (C). The participants completed the self-perception and experiential schemata assessment (SPESA) and source localization was compared utilizing standardized low-resolution electromagnetic tomography (sLORETA). The data show significant differences between groups during both the assessment condition and baselines. A pattern of alpha activity as estimated by sLORETA was shown in the right amygdala, uncus, hippocampus, BA37, insular cortex and orbitofrontal regions during the SPESA condition. This activity possibly reflects a circuit related to negative perceptions of self formed in specific neural pathways. These pathways may be responsive to the alpha activity induced by many substances by bringing the brain into synchrony if only for a short time. In effect this may represent the euphoria described by substance abusers.

Psychological improvements in patients with substance use disorders have been reported after neurofeedback treatment. However, neurofeedback has not been commonly accepted as a treatment for substance dependence. This study was carried out to examine the effectiveness of this therapeutic method for opiate dependence disorder. The specific aim was to investigate whether treatment leads to any changes in mental health and substance craving. In this experimental study with a pre-post test design, 20 opiate dependent patients undergoing Methadone or Buprenorphine maintenance treatment were examined and matched and randomized into two groups. While both experimental and control groups received their usual maintenance treatment, the experimental group received 30 sessions of neurofeedback treatment in addition. The neurofeedback treatment consisted of sensory motor rhythm training on Cz, followed by an alpha-theta protocol on Pz. Data from the general health questionnaire and a heroin craving questionnaire were collected before and after treatment. Multivariate analysis of covariance showed that the experimental group achieved improvement in somatic symptoms, depression, and total score in general mental health; and in anticipation of positive outcome, desire to use opioid, and relief from withdrawal of craving in comparison with the control group. The study supports the effectiveness of neurofeedback training as a therapeutic method in opiate dependence disorder, in supplement to pharmacotherapy.

This study examined the efficacy of a cardiorespiratory biofeedback intervention compared to bed rest in the treatment of 47 women diagnosed with pregnancy-induced hypertension (PIH). The investigation consisted of a historical control group with 31 PIH subjects receiving treatment as usual (TAU), bed rest and antihypertensive medications, and an experimental group with 16 PIH subjects receiving TAU and instruction on using a portable respiratory sinus arrhythmia (RSA) biofeedback device once daily until delivery. Results indicated that systolic and diastolic blood pressure levels were unchanged for either group. Failing to find the intended main effects, a series of exploratory analyses were performed. Findings of associated hypotheses revealed that the RSA BF group had a 35 % higher birth weight than the TAU group. The gestational age at delivery was 10 % greater in the RSA BF group than in the TAU group. A significant relationship was found between the StressEraser Total and the 1-min Apgar score. Eighty-one percent of the subjects stated that the device was relaxing. Fifty percent of the subjects believed that the device helped them fall asleep. Overall, these results suggest that portable RSA biofeedback may be effective in reducing stress during pregnancy and improving perinatal outcomes.

The primary diagnostic procedure for Attention-Deficit/Hyperactivity Disorder (ADHD) is the clinical interview, because psychological, neuropsychological, and neurological tests to date have not had sufficient specificity. Currently, there is no objective means to measure severity of ADHD, or the extent to which it is benefited by various dosages of medication. We recently reported that a certain EEG profile, the Consistency Index, occurring during the transition between two easy cognitive tasks clearly differentiated ADHD from non-ADHD boys between the ages of 8 and 12. The current study replicated this with older males (19-25) using different tasks, and a double blind, placebo versus Ritalin controlled crossover design. Seven ADHD subjects were found to have a significantly lower Consistency Index than 6 non-ADHD males while transitioning from 2 Simple tasks during placebo condition, while only the ADHD subjects demonstrated a significant improvement in their Consistency Index while on Ritalin. Similar but nonsignificant trends were observed while transitioning across Hard tasks.

Manifestations of ADHD are observed at both psychological and physiological levels and assessed via various psychometric, EEG, and imaging tests. However, no test is 100% accurate in its assessment of ADHD. This study introduces a stochastic assessment combining psychometric tests with previously reported (Consistency Index) and newly developed (Alpha Blockade Index) EEG-based physiological markers of ADHD. The assessment utilizes classical Bayesian inference to refine after each step the probability of ADHD of each individual. In a pilot study involving six college females with ADHD and six matched controls, the assessment achieved correct classification for all ADHD and non-ADHD participants. In comparison, the classification of ADHD versus non-ADHD participants was < 85% for any one of the tests separately. The procedure significantly improved the score separation between ADHD versus non-ADHD groups. The final average probabilities for ADHD were 76% for the ADHD group and 8% for the control group. These probabilities correlated (r = .87) with the Brown ADD scale and (r = .84) with the ADHD-Symptom Inventory used for the screening of the participants. We conclude that, although each separate test was not completely accurate, a combination of several tests classified correctly all ADHD and all non-ADHD participants. The application of the proposed assessment is not limited to the specific tests used in this study--the assessment represents a general paradigm capable of accommodating a variety of ADHD tests into a single diagnostic assessment.

In ADHD several EEG biomarkers have been described before, with relevance to treatment outcome to stimulant medication. This pilot-study aimed at personalizing neurofeedback treatment to these specific sub-groups to investigate if such an approach leads to improved clinical outcomes. Furthermore, pre- and post-treatment EEG and ERP changes were investigated in a sub-group to study the neurophysiological effects of neurofeedback. Twenty-one patients with ADHD were treated with QEEG-informed neurofeedback and post-treatment effects on inattention (ATT), hyperactivity/impulsivity (HI) and comorbid depressive symptoms were investigated. There was a significant improvement for both ATT, HI and comorbid depressive complaints after QEEG-informed neurofeedback. The effect size for ATT was 1.78 and for HI was 1.22. Furthermore, anterior individual alpha peak frequency (iAPF) demonstrated a strong relation to improvement on comorbid depressive complaints. Pre- and post-treatment effects for the SMR neurofeedback sub-group exhibited increased N200 and P300 amplitudes and decreased SMR EEG power post-treatment. This pilot study is the first study demonstrating that it is possible to select neurofeedback protocols based on individual EEG biomarkers and suggests this results in improved treatment outcome specifically for ATT, however these results should be replicated in further controlled studies. A slow anterior iAPF at baseline predicts poor treatment response on comorbid depressive complaints in line with studies in depression. The effects of SMR neurofeedback resulted in specific ERP and EEG changes.

Attention-Deficit/Hyperactivity Disorder (ADHD) is reported to have an incidence of 3-5%, and is associated with a variety of interpersonal, academic, and social problem behaviors. There is controversy as to whether ADHD is a learned behavioral or brain dysfunction. Research has explored a variety of measures to assess behavioral and brain dysfunctions in this population, with no consistent and clearly diagnostic results. We investigated whether a new psychometric and a new electroencephalographic procedure would clearly differentiate ADHD. The psychometric was based on DSM-IV criteria and the EEG measure was based on the assumption that ADHD interferes with cognitive transition from one discrete task to another. Parents of four ADHD boys (ages 8-12) and four age- and interest-matched non-ADHD boys completed the ADHD Symptom Inventory, while their sons' EEG was monitored during viewing of a video and reading of a book. For the ADHD boys, this was repeated a second time, 3 months later, to assess test-retest reliability. Both the psychometric and the EEG measures clearly differentiated the two samples (p's < .01) with no overlap in scores, were reliable over 3 months (r = .87), and were significantly correlated with one another (r = .85). While a small sample size, these robust, related and reliable findings suggest that both the psychometric and the psychophysiological EEG measures deserve further replication and exploration.

Behavioral and cognitive improvements in children with ADHD have been consistently reported after neurofeedback-treatment. However, neurofeedback has not been commonly accepted as a treatment for ADHD. This study addresses previous methodological shortcomings while comparing a neurofeedback-training of Theta-Beta frequencies and training of slow cortical potentials (SCPs). The study aimed at answering (a) whether patients were able to demonstrate learning of cortical self-regulation, (b) if treatment leads to an improvement in cognition and behavior and (c) if the two experimental groups differ in cognitive and behavioral outcome variables. SCP participants were trained to produce positive and negative SCP-shifts while the Theta/Beta participants were trained to suppress Theta (4-8 Hz) while increasing Beta (12-20 Hz). Participants were blind to group assignment. Assessment included potentially confounding variables. Each group was comprised of 19 children with ADHD (aged 8-13 years). The treatment procedure consisted of three phases of 10 sessions each. Both groups were able to intentionally regulate cortical activity and improved in attention and IQ. Parents and teachers reported significant behavioral and cognitive improvements. Clinical effects for both groups remained stable six months after treatment. Groups did not differ in behavioural or cognitive outcome.

The objective of the present paper was to develop a differential electromyographic biofeedback (EMG-BF) training for children with attention-deficit/hyperactivity disorder (ADHD) matching multiple neurofeedback training protocols in order to serve as a valid control training. This differential EMG-BF training method feeds back activity from arm muscles involved in fine motor skills such as writing and grip force control. Tonic EMG-BF training (activation and deactivation blocks, involving bimanual motor tasks) matches the training of EEG frequency bands, while phasic EMG-BF training (short activation and deactivation trials) was developed as an equivalent to the training of slow cortical potentials. A case description of a child who learned to improve motor regulation in most task conditions and showed a clinically relevant reduction of behavioral ADHD symptoms illustrates the training course and outcome. Differential EMG-BF training is feasible and provides well-matched control conditions for neurofeedback training in ADHD research. Future studies should investigate its value as a specific intervention for children diagnosed with ADHD and comorbid sensorimotor problems.

This study continues our research to further validate the idea that ADHD (Attention Deficit/Hyperactivity Disorder) interferes with transition from one task to another and this interference can be quantified by a Consistency Index (CI) derived from a specific mathematical representation of EEG data. We reanalyze 32 previously reported data sets present new data for 35 boys and girls, ages 7-12, ADHD or control. Each data set contains EEG, recorded and digitized while participants perform consecutive 10-min tasks: video, reading, and math. For boys, the CI in ADHD was four times lower than in controls, p < .005, for girls this difference was two times, p < .05. ADHD/control classification based on the CI coincided with the DSM-IV criteria for 88% of the boys and for 67% of the girls. Post hoc analysis indicated that the classification utility of the CI diminished with age. A CI below 40% could be a discriminating, reliable, and reproducible marker of ADHD in young boys.

The goal of this study was to investigate psychophysiological characteristics in chronic pain patients during a pain stressor (cold pressor test) and after a brief diaphragmatic breathing intervention. Laboratory procedures were designed to quantify the effects of diaphragmatic breathing training at six breaths per minute on cardiac autonomic reactivity as indexed by root mean square of successive differences (RMSSD) and sequential baroreflex sensitivity (sBRS). Participants (n = 22) completed an initial laboratory assessment including the diaphragmatic breathing training session and were instructed to practice the technique for three ten-minute sessions daily. Self-monitoring of the use of the technique along with daily pain and fatigue scores was accomplished with hand-held computers. Participants returned to the lab for a second assessment after two-weeks. Participants demonstrating improved resting physiological status as indexed by change in RMSSD and sBRS after training (improvers) were compared to those not demonstrating any change in these variables (non-improvers). After two weeks of training, the improvers showed higher tolerance (p < .05) and lower blood pressure reactivity to the cold pressor test (p < .05) compared to the non-improvers. Time spent practicing the breathing technique was significantly different between the groups with the improvers maintaining daily practice close to the intervention recommendations. These results suggest the potential for significant improvements in autonomic functioning and inhibitory response to stress after a single intervention session and two weeks of practice.