Heart rate variability does not tap putative efficacy of Thought Field Therapy.

Callahan (2001) has offered a series of case reports in an effort to validate the rationale and methods of Thought Field Therapy (TFT). These case reports employ subjective ratings, that is, the Subjective Units of Distress (SUD) rating scale as well as a gross measure of heart rate variability (HRV). My criticisms center around (a) inappropriately strong inferences given exclusive reliance on case reports, a potentially biased sample, and lack of appropriate controls; (b) misinterpretation of statistical artifact as systematic effect; (c) lack of systematic evaluation of HRV changes; and (d) erroneous interpretation of HRV. Callahan's article provides no evidence for the efficacy of TFT nor does it provide evidence for the credibility of TFT's rationale.

Anterior electroencephalographic asymmetry changes in elderly women in response to a pleasant and an unpleasant odor.

Greater left than right frontal EEG activation has been associated with increased positive and/or decreased negative affect, whereas greater right than left frontal activation has been associated with the opposite pattern. Substantial research has documented the trait properties of asymmetry, as well as responses to pleasant and unpleasant stimuli. The present study examined changes in anterior alpha asymmetries in response to pleasant (vanilla), unpleasant (valerian), and neutral (water) odors. As predicted, vanilla produced relative left frontal activation compared to valerian and water. Frontal asymmetry did not differ in response to valerian compared to water. The results are consistent with the hypothesis that the left frontal region of the brain is involved in positive/approach-related emotion, and extend previous results into the olfactory realm.

Electroencephalographic registration of low concentrations of isoamyl acetate.

Previous research has demonstrated electroencephalogram (EEG) changes in response to low-odor concentrations, resulting in near-chance detection. Such findings have been taken as evidence for olfaction without awareness. We replicated and extended previous work by examining EEG responses to water-water control, 0.0001, 0. 001, 0.01, and 1 ppm isoamyl acetate (IAA) in water paired with water only. Detection was above chance (>50%) for.001 and above, and alpha decreased only to those concentrations, suggesting that EEG changes corresponded to IAA awareness. However, when correct trial EEGs were compared to incorrect trial EEGs during.001 ppm, right posterior/central alpha decreased during incorrect trials and alpha decreased more globally (including frontal sites) during correct trials. These data may not reflect awareness or unawareness per se. Instead, results are discussed regarding activation of perceptual systems in the posterior region during incorrect trials and the activation of frontal action systems during a subset of correct trials.

Gender specificity of resting anterior electroencephalographic asymmetry and defensiveness in the elderly.

OBJECTIVE: It has been reported that defensiveness in women is associated with relative left-frontal electroencephalogram (EEG) activation, while defensiveness in men is associated with relative right-frontal EEG activation. The present study examined whether this result generalized to men and women between the ages of 58 and 70. DESIGN: The Marlowe-Crowne Social Desirability Scale (MCSD) and EEG testing were used to examine relationships between gender, defensiveness, and anterior asymmetry. PARTICIPANTS: Men (n = 18) and women (n = 54) between the ages of 58 and 70 (mean age = 64.22, standard deviation = 3.003) were recruited from Tucson and surrounding areas of Pima County, Arizona. They were selected from among participants in an integrative health sciences study of aging that took place between 1991 and 1993. METHOD: Subjects were divided into high-defensive and low-defensive groups based on a median split on the MCSD. EEGs were recorded from 19 channels (standard 10-20 montage), referenced to linked ears, and digitalized on-line at 128 Hz (band pass 2-32 Hz) during consecutive 60-second eyes-open and eyes-closed baselines. Two-second epochs containing bioelectric artifacts > 50 microvolts were eliminated from analyses. Average alpha (8-13 Hz) power (microV2)) was computed by Fast Fourier Transform and natural log (ln) transformed for normalization. Asymmetry scores were computed (log[right]-log[left]) for F4-F3, Fp2-Fp1, F8-F7, C4-C3, T4-T3, T6-T5, P4-P3, and O2-O1 for aggregated eyes-open and eyes-closed baselines. R-L asymmetry scores were analyzed for the aggregate frontal lead pairs, as well as for each pair separately. RESULTS: Findings were similar to those previously reported in that the direction of the relationship in men and women was the same. The results differed in that we found left-frontal activation in low-defensive men, whereas the previous study found right-frontal activation in high-defensive men. Furthermore, although in the same direction, the relationship for women was nonsignificant. CONCLUSION: These differences may have been due to the age of the participants, a lax impedence criterion, or the use of the MCSD rather than the L scale of the Eysenck Personality Questionnaire, as in the earlier study. Nevertheless, the findings suggest that gender differences in the relationship between resting anterior EEG asymmetry and defensiveness may persist throughout the life span.

Repressive and defensive coping styles predict resting plasma endorphin levels in the elderly.

Jamner, L.D., Schwartz, G.E., 1986, Psychosom. Med. 48, 211-223, have proposed that repressive and defensive coping are associated with greater central endogenous opioid activity. They reasoned that high-defensive (HD) participants' attenuated distress, increased pain tolerances, attenuated somatic symptomatology, and accentuated reports of positive emotions are consistent with actions of centrally active opioid peptides. The present study assessed plasma beta-endorphin (END) levels, Marlowe Crowne Social Desirability Scale (MCSD), and Taylor Manifest Anxiety Scale (TMAS) scores in men (n = 6) and women (n = 20) between the ages of 59 and 79. Contrary to predictions, HD had lower plasma endorphin levels than did low-defensive (LD) participants. Raw MCSD scores correlated negatively with endorphin levels. Findings were significant for women only, which may have been due to the small sample of men. The results are discussed as they related to the hypothesis that defensiveness involves alteration of central opioid systems.

Is left frontal brain activation in defensiveness gender specific?

A. J. Tomarken and R. J. Davidson (1994) reported that defensiveness is characterized by relative left frontal brain activation. Because they examined only women, gender differences in this relation are possible. In the present study, resting alpha asymmetries in right-handed men (n = 25) and women (n = 60) were related to defensiveness, measured by the Eysenck Personality Questionnaire L scale. These results were similar to those of Tomarken and Davidson in that defensiveness correlated positively with relative left frontal activation in women. An unexpected finding was that high-defensive men showed relative right frontal activation, a result virtually opposite that for women. These results imply that the nature of defensiveness as a coping strategy may vary as a function of gender.

Quantitative EEG patterns during nose versus mouth inhalation of filtered room air in young adults with and without self-reported chemical odor intolerances.

Individuals who report illness (e.g. nausea, headache) from common chemical odors tend to report CNS symptoms suggestive of olfactory-limbic system involvement. This study compared the resting quantitative electroencephalographic (qEEG) patterns of young adult college students reporting subjectively elevated chemical odor intolerance ratings (HICI) with those of controls reporting little or no odor intolerance (LOCI). Each group was subdivided into those with higher (HIDEP) vs. lower (LODEP) ratings of concomitant depression. Nineteen channels of EEG were recorded during a single session over four separate rest periods, respectively, following baseline, cognitive, chemical exposure and olfactory identification tests. Each recording involved two 30-s, eyes-closed, filtered room air breathing conditions: (1) nose inhalation followed by mouth exhalation and (2) mouth inhalation followed by mouth exhalation. HICI showed significantly less beta 1 (beta 1) over the temporal-central region during nose than during mouth inhalation. Over some temporal and central leads, task, DEP and CI interacted to influence beta 1 as well. For theta (theta), CI differences emerged during nose inhalation after the cognitive task at Cz, after chemical exposures at C3, Cz and C4 and after the olfactory ID task at C4. CI differences emerged during mouth breathing after the olfactory ID task at Cz, C4 and T4. The T5-T6 coronal array showed significant CI differences after chemical exposures during nose breathing and during mouth breathing after the cognitive and olfactory ID tasks. The theta findings in the HICI may be related to reports of disturbed attention in CI.

Differential resting quantitative electroencephalographic alpha patterns in women with environmental chemical intolerance, depressives, and normals.

BACKGROUND: Previous research suggests that a subset of individuals with intolerance to low levels of environmental chemicals have increased levels of premorbid and/or comorbid psychiatric disorders such as depression, anxiety, and somatization. The purpose of this study was to evaluate the psychological profiles and quantitative electroencephalographic (qEEG) profiles at baseline of women with and without chemical intolerance (CI). METHODS: Participants were middle-aged women who reported illness from the odor of common chemicals (CI, n = 14), depressives without such intolerances (D, n = 10), and normal controls (N, n = 11). They completed a set of psychological scales and underwent two separate qEEG recording laboratory sessions spaced 1 week apart, at the same time of day for each subject. RESULTS: CI were similar to D with increased lifetime histories of physician-diagnosed depression (71% vs. 100%), Symptom Checklist 90 (revised) (SCL-90-R) somatization scores, Barsky Somatic Symptom Amplification, and perceived life stressfulness, although D had more distress than either CI or N on several other SCL-90-R subscales. CI scored significantly higher on the McLean Limbic Symptom Checklist somatic symptom subscale than did either D or N. On qEEG, CI exhibited significantly greater overall resting absolute alpha activity with eyes closed, especially at the parietal midline site (Pz), and increased (sensitized) frontal alpha from session 1 to 2, in contrast with the D and N groups. D showed right frontal asymmetry in both sessions, in comparison with CI. CONCLUSIONS: The data indicate that CI with affective distress diverge from both D without chemical intolerance and N in qEEG alpha patterns at resting baseline. Although CI descriptively resemble D with increased psychological distress, the CI's greater alpha suggests the possibility of a) central nervous system hypo-, not hyper-, activation; and/or b) an overlap with EEG alpha patterns of persons with positive family histories of alcoholism.

Individual differences in neural sensitization and the role of context in illness from low-level environmental chemical exposures.

This paper summarizes the clinical phenomenology of multiple chemical sensitivity (MCS), outlines the concepts and evidence for the olfactory-limbic, neural sensitization model for MCS, and discusses experimental design implications of the model for exposure-related research. Neural sensitization is the progressive amplification of responsivity by the passage of time between repeated, intermittent exposures. Initiation of sensitization may require single toxic or multiple subtoxic exposures, but subsequent elicitation of sensitized responses can involve low or nontoxic levels. Thus, neural sensitization could account for the ability of low levels of environmental chemicals to elicit clinically severe, adverse reactions in MCS. Different forms of sensitization include limbic kindling of seizures (compare temporal lobe epilepsy and simple partial seizures) and time-dependent sensitization of behavioral, neurochemical, immunological, and endocrinological variables. Sensitized dysfunction of the limbic and mesolimbic systems could account in part for many of the cognitive, affective, and somatic symptoms in MCS. Derealization (an alteration in perception making familiar objects or people seem unfamiliar or unreal) is a common MCS symptom and has been linked with limbic dysfunction in clinical neuroscience research. Sensitization is distinct from, but interactive with, other neurobiological learning and memory processes such as conditioning and habituation (compare adaptation or tolerance). In previous studies, hypotheses for MCS involving sensitization, conditioning, and habituation (adaptation) have often been considered in isolation from one another. To design more appropriate chemical exposure studies, it may be important to integrate the various theoretical models and empirical approaches to MCS with the larger scientific literature on individual differences in these potentially interactive phenomena.

EEG responses to low-level chemicals in normals and cacosmics.

Recent studies from the University of Arizona indicate that normal subjects, both college students and the elderly, can register the presence of low-intensity odors in the electroencephalogram (EEG) in the absence of conscious awareness of the odors. The experimental paradigm involves subjects sniffing pairs of bottles, one containing an odorant (e.g. isoamyl acetate) dissolved in an odorless solvent (water or liquid silicone), the other containing just the solvent, while 19 channels of EEG are continuously recorded. For the low-intensity odor conditions, concentrations are adjusted downward (decreased) until subjects correctly identify the odor bottle at chance (50%). The order of odorants, concentrations, and hand holding the control bottle, are counterbalanced within and across subjects. Three previous experiments found that alpha activity (8-12 hz) decreased in midline and posterior regions when subjects sniffed the low-intensity odors. The most recent study suggests that decreased theta activity (4-8 hz) may reflect sensory registration and decreased alpha activity may reflect perceptual registration. In a just completed experiment involving college students who were selected based on combinations of high and low scores on a scale measuring cacosmia (chemical odor intolerance) and high and low scores on a scale measuring depression, cacosmic subjects (independent of depression) showed greater decreases in low-frequency alpha (8-10 hz) and greater increases in low-frequency beta (12-16 hz) to the solvent propylene glycol compared to an empty bottle. Topographic EEG mapping to low-intensity odorants may provide a useful tool for investigating possible increased sensitivity to specific chemicals in chemically sensitive individuals.

Event-related potential amplitude/intensity slopes predict response to antidepressants.

We measured event-related potential (ERP) component amplitudes to four intensities of randomly presented tones. Patients diagnosed with major depressive disorder were tested prior to and following a clinical trial of antidepressant medication. Slope of P2 amplitude as a function of stimulus intensity was calculated for each subject and condition. Subjects were divided into two groups (responders and nonresponders) based on their Hamilton Rating Scale for depression scores following treatment. Responders had significantly larger P2 slopes prior to treatment than did nonresponders. P2 slopes did not differ significantly between responders and nonresponders following antidepressant treatment. These data support the conclusion that P2 amplitude/intensity slope may be a predictor of response to treatment with antidepressant medication.

Defensiveness, anxiety and the amplitude/intensity function of auditory-evoked potentials.

This study measured relationships between defensiveness, anxiety, and auditory-evoked potentials to tones of varied intensity. Subjects were designated as defensive if they scored > or = 7 on the L-scale of the Eysenck Personality Questionnaire, and high-anxious if they scored > or = 11 on the N-scale. Four groups resulted: 'high anxious', 'defensive high anxious', 'repressors' (i.e., defensive low anxious) and 'low anxious'. Evoked potentials were recorded from FZ, CZ, PZ, C3, C4, T3 and T4, referenced to linked ears in response to 74, 84, 94 and 104 dB SPL tones. High-defensive subjects showed lower P2 amplitudes to the 94 and 104 dB tones and lower amplitude/intensity slopes at FZ, CZ, C3 and C4. High-anxious subjects showed lower P2 amplitudes to all four stimulus intensities at FZ, CZ and PZ. The results are consistent with the hypothesis that defensiveness is associated with desensitization to intense or painful stimulation.