This report describes the use of neurofeedback therapy to reduce the electroencephalographic (EEG) theta/sensorimotor rhythm (SMR) ratio for patients who present with NEE. The effectiveness of neurofeedback therapy to reduce theta band (4-7 Hz) activity and enhance SMR (12-14 Hz) activity, as measured at location Cz (International 10/20 system), in the treatment of epilepsy is documented (Sterman 1986), although no data are available for pseudoseizure patients. The case studies to be reported below are consistent with the population of patients reported by Bowman and Markand (1996). All had long histories of therapeutic intervention with limited success. Further, EEG assessments showed no epileptiform activity before, during, or following a seizure. All presented with significant comorbidity and poorly explained seizure onset in adulthood, and all have had multiple psychiatric hospitalization.
A treatment protocol was developed to modify the theta/SMR ratio, which included brainwave disentrainment (Rozelle and Burzynski 1995) and neurofeedback (Ayers 1993). Brainwave disentrainment involves measuring the dominant EEG frequency (DF) (i.e., maximum amplitude averaged over 1-sec epochs) and stimulating the client with light-emitting diode goggles and sounds at a frequency either 5% greater than or 5% less than the DF. These multipliers (i.e., + or – 5%) alternate every minute, with the result that the brain’s DF extends over a wider range. The purpose of this procedure is to enhance neuronal flexibility and normalize the EEG (Tachiki et al 1994). Positive results from the procedure have been reported for the treatment for mild head injury (Ochs 1994) and learning disability (Russell et al 1994).
Figure 1. Skin conductivity level (SCL) during auditory stimulation of a client with pseudoseizure disorder.
The neurofeedback protocol is based on the work of Sterman (1986) and Ayers (1993). It involves the suppression of the theta band activity concordantly with the enhancement of SMR band activity. Neuronal feedback to the patient occurred when SMR band activity exceeded a set threshold and when theta band activity was below a set threshold. A monopolar montage was used with the active electrode at Cz (International 10/20 system). Frequency of treatment was between one and three times per week. Notably, all were being treated concurrently with psychotherapy during the adjunctive theta/SMR training.
The patient, a Caucasian woman in her early forties, experiences a variety of seizure-like episodes that occur with normal waking EEG architecture. The patient has identified several NEE subtypes, including fugue-like states, a loss or compromise of motor and/or cognitive control, and episodes of rage. The severe NEE typically involve collapsing to the floor with the body assuming a fetal position. In that position the torso convulses and the arms and/or legs may thrash about. Typically these severe NEE last from several seconds to several minutes and may occur repeatedly. This patient has been hospitalized for various psychiatric complaints over 10 times during the last 10 years. This patient has a long and significant history of severe physical , psychological, and sexual abuse. This patient was intolerant of light and sound stimulation, a condition often observed in posttraumatic stress disorder patients. Her tolerance of various sounds was assessed while electrodermal activity (EDR) was measured, from both hands, using a constant voltage electrodermal monitor. As noted in Figure 1, seizures occurred when the EDR was greater than about 4 mho in either hand. A procedure for reducing autonomic arousal (Swingle 1994), which includes the presentation of subthreshold sounds and/or somatosensory stimulation, was presented during the auditory stimulation.
Figure 2. Skin conductivity level (SCL) during auditory stimulation of a client with pseudoseizure disorder.
Figure 2 shows the EDR level for one session in which arousal was reduced while sound stimulation was presented. The protocol maintained the EDR below 4 mho, and no seizures were observed.
The outcome data, separated into four categories, are from very detailed records maintained by the patient at the suggestion of her neuroendocrinologist in September of 1993. The four categories are the total number of seizures, SFD, MS (3 or more per day), and SS. After 11 months of treatment (modal frequency once per week) SFD increased by 15%, MS decreased by 8%, and the total number of seizures per month decreased by 30% (t < 2.5, df = 8, p < .05 in all cases).
The patient was able to modify her theta/SMR ratio during the disentrainment and neurofeedback treatment. The average theta/SMR ratio recorded during pretreatment baseline on each day of treatment for the first 3 months (mean = 1.96, SD = 0.12) and for the last 3 months of treatment (mean = 1.55, SD – 0.20) were found to be significantly different (t = 3.55, df = 23, p < .01). As the data in Table 1 indicate, the theta/SMR ratio correlates with SS and the total number of seizures, marginally with MS, but not with SFD.
The daily seizure totals were also compared with the theta/SMR average on the days of EEG treatment. The theta/SMR ratio for days when no seizures were reported (mean = 1.46, SD = 0.113) differed significantly (t = 2.87, df = 28, p < .02) from seizure days (mean = 1.68, SD = 0.228).
Table 1. Spearman Rank-Order Correlations between Theta/SMR ratio and categories of Reported Seizure Activity
Category of seizure activity Coefficient p