Philipp M. Keune

Mindfulness-based interventions in multiple sclerosis: beneficial effects of Tai Chi on balance, coordination, fatigue and depression

BackgroundPatients suffering from Multiple Sclerosis (MS) experience a wide array of symptoms, including balance problems, mobility impairment, fatigue and depression. Physical exercise has recently been acknowledged as a treatment option complementary to medication. However, information regarding putative effects of structured exercise programs on neurological symptoms is sparse. Tai Chi, a Chinese martial art incorporating physical exercise and mindfulness training, has been shown to yield health benefits in various neurological groups. It seems particularly suitable for patients with motoric deficits as it challenges coordination and balance. The purpose of the current study was to explore the therapeutic value of structured Tai Chi training for coordination, balance, fatigue and depression in mildly disabled MS patients.MethodsA sample of 32 MS patients (Expanded Disability Status Scale, EDSS < 5) was examined. A structured Tai Chi course was devised and a Tai Chi group participated in two weekly sessions of 90 minutes duration for six months, while a comparison group received treatment as usual (TAU). Both groups were examined prior to and following the six-months interval with regards to balance and coordination performance as well as measures of fatigue, depression and life satisfaction.ResultsFollowing the intervention, the Tai Chi group showed significant, consistent improvements in balance, coordination, and depression, relative to the TAU group (range of effect-sizes: partial η2 = 0.16 – 0.20). Additionally, life satisfaction improved (partial η2 = 0.31). Fatigue deteriorated in the comparison group, whereas it remained relatively stable in the Tai Chi group (partial η2 = 0.24).ConclusionsThe consistent pattern of results confirms that Tai Chi holds therapeutic potential for MS patients. Further research is needed to determine underlying working mechanisms, and to verify the results in a larger sample and different MS subgroups.

Frontal brain asymmetry in adult attention-deficit/hyperactivity disorder (ADHD): Extending the motivational dysfunction hypothesis

OBJECTIVE Attention-deficit/hyperactivity disorder (ADHD) involves motivational dysfunction, characterized by excessive behavioral approach tendencies. Frontal brain asymmetry in the alpha band (8-13 Hz) in resting-state electroencephalogram (EEG) represents a neural correlate of global motivational tendencies, and abnormal asymmetry, indicating elevated approach motivation, was observed in pediatric and adult patients. To date, the relation between ADHD symptoms, depression and alpha asymmetry, its temporal metric properties and putative gender-specificity remain to be explored. METHODS Adult ADHD patients (n=52) participated in two resting-state EEG recordings, two weeks apart. Asymmetry measures were aggregated across recordings to increase trait specificity. Putative region-specific associations between asymmetry, ADHD symptoms and depression, its gender-specificity and test-retest reliability were examined. RESULTS ADHD symptoms were associated with approach-related asymmetry (stronger relative right-frontal alpha power). Approach-related asymmetry was pronounced in females, and also associated with depression. The latter association was mediated by ADHD symptoms. Test-retest reliability was sufficient. CONCLUSIONS The association between reliably assessable alpha asymmetry and ADHD symptoms supports the motivational dysfunction hypothesis. ADHD symptoms mediating an atypical association between asymmetry and depression may be attributed to depression arising secondary to ADHD. Gender-specific findings require replication. SIGNIFICANCE Frontal alpha asymmetry may represent a new reliable marker of ADHD symptoms.

Normative data and long-term test-retest reliability of the triple stimulation technique (TST) in multiple sclerosis.

OBJECTIVES Transcranial magnetic stimulation is useful for the assessment of cortico-spinal tract integrity in multiple sclerosis (MS). An advanced approach is the triple stimulation technique (TST), utilizing a combination of central and peripheral stimuli, reducing individual response variability. Although TST measures have been implemented in longitudinal studies, basic methodological data on temporal properties of abnormal TST values in MS are sparse. METHODS Normative TST data were obtained from 48 healthy participants. Longitudinal measures were derived from 17 MS-patients (relapsing-remitting: N=10; clinically isolated syndrome: N=7) prior to, three and twelve months following therapy initiation. Intraclass correlations were used to examine test-retest reliability. Complementary, patient ambulation and cognition were assessed. RESULTS Patient TST parameters were abnormal, involving excellent test-retest reliability and stable mean values. Cognitive and motor performance improved. CONCLUSIONS Results are the first to show that abnormal TST values in MS, reflecting diagnostic utility, are highly reliable in a long-term follow-up. Methodological properties are adequate for a longitudinal implementation of TST. Parameters were insensitive to alterations in cognitive/motor functioning. Sensitivity may be verified in subgroups with different treatment regimes. SIGNIFICANCE Results provide new normative data, support diagnostic utility of TST measures in MS, and confirm their long-term robustness.

Exploring resting-state EEG brain oscillatory activity in relation to cognitive functioning in multiple sclerosis

OBJECTIVE Neurophysiologic monitoring parameters related to cognition in Multiple Sclerosis (MS) are sparse. Previous work reported an association between magnetoencephalographic (MEG) alpha-1 activity and information processing speed. While this remains to be replicated by more available electroencephalographic (EEG) methods, also other established EEG markers, e.g. the slow-wave/fast-wave ratio (theta/beta ratio), remain to be explored in this context. METHODS Performance on standard tests addressing information processing speed and attention (Symbol-Digit Modalities Test, SDMT; Test of Attention Performance, TAP) was examined in relation to resting-state EEG alpha-1 and alpha-2 activity and the theta/beta ratio in 25MS patients. RESULTS Increased global alpha-1 and alpha-2 activity and an increased frontal theta/beta ratio (pronounced slow-wave relative to fast-wave activity) were associated with lower SDMT processing speed. In an exploratory analysis, clinically impaired attention was associated with a significantly increased frontal theta/beta ratio whereas alpha power did not show sensitivity to clinical impairment. CONCLUSIONS EEG global alpha power and the frontal theta/beta ratio were both associated with attention. The theta/beta ratio involved potential clinical sensitivity. SIGNIFICANCE Resting-state EEG recordings can be obtained during the routine clinical process. The examined resting-state measures may represent feasible monitoring parameters in MS. This notion should be explored in future intervention studies.

Frontal alpha asymmetry and callous-unemotional traits in imprisoned violent offenders: A pilot study

Based on the approach-withdrawal model of hemispheric asymmetry, anger and aggression have been linked to an approach-related pattern, characterized by stronger relative left-hemispheric anterior cortical activity. Recent work suggests that also in individuals with extremely violent tendencies, such as imprisoned offenders, approach-related asymmetry may be associated with self-reported trait anger and aggression. A putative association between alpha asymmetry and further characteristics relevant for aggression, such as callous-unemotional (CU) traits, remains to be explored. CU traits may increase the probability of aggressive behavior; nevertheless, they may also enable individuals to inhibit and postpone the overt display of aggression until circumstances grant its strongest impact. In the current exploratory study, we measured trait aggression, CU traits, and resting-state EEG asymmetry in the alpha band (8-13 Hz) in imprisoned violent offenders in a German high security prison. Results revealed that particularly trait callousness was associated with stronger relative right-hemispheric anterior cortical activity (i.e., a withdrawal-related pattern). An association between alpha asymmetry and aggression was not replicated. These preliminary findings suggest that, due to the involved emotional and interpersonal detachment, callousness might be withdrawal related, despite its potential to bring about aggressive behavior. They also imply that the identification of putative clinical subtypes in prisoners is required, as varying psychopathology might undermine an association between alpha asymmetry and aggression.

Measuring standing balance in multiple sclerosis: Further progress towards an automatic and reliable method in clinical practice

BACKGROUND Balance deficits in multiple sclerosis (MS) are often monitored by means of observer-rated tests. These may provide reliable data, but may also be time-consuming, subject to inter-rater variability, and potentially insensitive to mild fluctuations throughout the clinical course. On the other hand, laboratory assessments are often not available. The Nintendo Wii Balance Board (WBB) may represent a low-cost solution. The purpose of the current study was to examine the methodological quality of WBB data in MS (internal consistency, test-retest reliability), convergent validity with observer-rated tests (Berg Balance Scale, BBS; Timed-Up and Go Test, TUG), and discriminative validity concerning clinical status (Expanded Disability Status Scale, EDSS). METHODS Standing balance was assessed with the WBB for 4min in 63 MS patients at two assessment points, four months apart. Additionally, patients were examined with the BBS, TUG and the EDSS. RESULTS A period of 4min on the WBB provided data characterized by excellent internal consistency and test-retest reliability. Significant correlations between WBB data and results of the BBS and TUG were obtained after merely 2min on the board. An EDSS median-split revealed that higher EDSS values (>3) were associated with significantly increased postural sway on the WBB. CONCLUSIONS WBB measures reflecting postural sway are methodologically robust in MS, involving excellent internal consistency and test-retest reliability. They are also characterized by convergent validity with other considerably lengthier observer-rated balance measures (BBS) and sensitive to broader clinical characteristics (EDSS). The WBB may hence represent an effective, easy-to-use monitoring tool for MS patients in clinical practice.

Frontal EEG alpha asymmetry and emotion: From neural underpinnings and methodological considerations to psychopathology and social cognition

Forty years ago, in September of 1978, at the annual meeting of the Society for Psychophysiological Research inMadison,Wisconsin, the early-career scientist Richie Davidson presented a paper suggesting that the experience of positive affect and of negative affect were associated with differently lateralized patterns of frontal brain electrical activity. Following the publication of the abstract of this presentation on frontal EEG asymmetry the next year (Davidson, Schwartz, Saron, Bennett, & Goleman, 1979), there were almost no publications in the following decade, with only 15 empirical articles examining frontal EEG asymmetry and emotion by 1990. It might have been hard to predict at that time how popular this measure of frontal brain asymmetry would become, with now hundreds of articles published using frontal EEG asymmetry to examine emotion-related and motivation-related trait individual differences and staterelated changes. Among other topics, frontal EEG asymmetry has been used to investigate risk for depression, anxiety, and internalizing psychopathology, as well as externalizing disorders such as mania, addiction, and attention-deficit hyperactivity disorder (ADHD). It has also been used extensively to examine individual differences in temperament and motivational style, and responses to emotional stimuli and social provocation. An advantage of frontal EEG asymmetry is its association with a highly successful conceptual model of emotion and motivation. The approach-withdrawal model of frontal asymmetry posits that increased relative left-frontal activity indicates a propensity to approach or engage a stimulus, whereas decreased relative left-frontal activity indicates a propensity toward reduced approach motivation or increased withdrawal motivation (e.g., Coan & Allen, 2004; Davidson, 1998; HarmonJones, 2003). Thus, frontal EEG asymmetry involves a unidimensional metric capturing large variations in motivation, emotion, and behavior. This metric is not only useful in understanding normative variation in motivation and emotion, but also abnormal variation, including mania and depression. Additionally, frontal asymmetry can be assessed as both a traitlike individual differences variable and as a measure of staterelated variation to particular stimuli or experimental paradigms (Coan & Allen, 2004; Coan, Allen, & McKnight, 2006).

Confusion regarding operant conditioning of the EEG – Authors' reply

Michael Schönenberg and colleagues report a trial of neurofeedback for the treatment of adults with attention-deficit hyperactivity disorder (ADHD). Neurofeedback and sham-feedback were triple blinded, and participants were unaware, via a deception protocol, that sham feedback was one intervention. Surprisingly, the authors did not assess participants’ perceptions of the deception, even though in a previous study with sham feedback as the control group done by one of the authors, Logemann, the majority of participants in both groups thought that they were in the sham group. Similarly, four other sham feedback-controlled trials found that most neurofeedback participants thought that they received sham feedback. This consistency suggests something profoundly amiss about the authors’ so-called verum (ie, true) neurofeedback methodology. This is a key observation made by Arns and colleagues, but dismissed by Schönenberg and colleagues. The authors’ state neurofeedback “is based on the assumption that deviant brain activity patterns can be voluntarily modulated by operant learning strategies” and used auto-thresholding, reset every 15 s, to maintain an 80% reward level for verum participants. The authors’ electroencephalographic (EEG) training method violates the established science of operant conditioning. The every 15 s reset delivered operant consequences to participants’ brains counter to the goal of training. If the targeted EEG was strengthening, reinforcement was withdrawn and reset down to 80%, thereby punishing participants for learning to self-modulate. Conversely, if the targeted EEG was decreasing, participants were reinforced up to 80%, thereby rewarding them for decreasing its strength. Not surprisingly, therefore, Schönenberg and colleagues found no evidence that participants learned to self-modulate the targeted EEG. Their findings are in substantial contrast with neurofeedback studies whose methodology mirror the best practices of operant conditioning. These studies consistently find that patients with ADHD learn to self-modulate the targeted brain activity and this learning is sustained during follow-up. 5 We hope that the authors will acknowledge that their neurofeedback methodology violates the very essence of operant conditioning or explain the errors in our analysis. At a minimum, we hope that all can agree there is no need for any future wasted research effort, or journal space, on more sequels using these methods. The literature needs a competent appraisal of neurofeedback’s efficacy in treating ADHD.

Cognitive screening in Multiple Sclerosis: the Five-Point Test as a substitute for the PASAT in measuring executive function

Abstract Objective: The Paced Auditory Serial Addition Test (PASAT) is frequently employed to measure executive functions in patients with Multiple Sclerosis (MS). In the past, the PASAT has often been criticized because of its stressful and demanding requirements. Continuous utilization might also reduce its validity. The Five-Point Test (FPT) by Regard, Strauss, and Knapp ((1982) Children’s production on verbal and non-verbal fluency tasks. Perceptual and Motor Skills, 55, 839–844.) is a short test of figural fluency which might serve as a substitute.Method: 116 patients diagnosed with MS were tested with a short version of the Brief Repeatable Battery (BRB) by Rao and the Cognitive Function Study Group of the National Multiple Sclerosis Society including the PASAT, as well as the FPT. A factor analysis was computed and the frequency of cognitive impairment was calculated for both the original short version of the BRB and the alternative version (involving the FPT).Results: In the factor analysis, PASAT and FPT loaded highest on the same factor (two factors were extracted). The estimation of the frequency of cognitive impairment showed that replacing the PASAT with the FPT did not considerably alter the proportion of patients identified as cognitively impaired.Conclusions: The FPT proved to be a viable alternative to the PASAT in this study. It may be recommended as a possible replacement in neuropsychological screening of MS-patients with the advantage of avoiding the indicated limitations of the PASAT.