Optimizing real time fMRI neurofeedback for therapeutic discovery and development

While reducing the burden of brain disorders remains a top priority of organizations like the World Health Organization and National Institutes of Health, the development of novel, safe and effective treatments for brain disorders has been slow. In this paper, we describe the state of the science for an emerging technology, real time functional magnetic resonance imaging (rtfMRI) neurofeedback, in clinical neurotherapeutics. We review the scientific potential of rtfMRI and outline research strategies to optimize the development and application of rtfMRI neurofeedback as a next generation therapeutic tool. We propose that rtfMRI can be used to address a broad range of clinical problems by improving our understanding of brain–behavior relationships in order to develop more specific and effective interventions for individuals with brain disorders. We focus on the use of rtfMRI neurofeedback as a clinical neurotherapeutic tool to drive plasticity in brain function, cognition, and behavior. Our overall goal is for rtfMRI to advance personalized assessment and intervention approaches to enhance resilience and reduce morbidity by correcting maladaptive patterns of brain function in those with brain disorders.

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Guidelines are proposed for studies of rtfMRI neurofeedback for clinical therapeutics.

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Evidence-based guidelines are needed for clinical trials of rtfMRI neurofeedback.

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These guidelines will shape the design of future clinical trials.

Orbitofrontal cortex neurofeedback produces lasting changes in contamination anxiety and resting-state connectivity

Anxiety is a core human emotion but can become pathologically dysregulated. We used functional magnetic resonance imaging (fMRI) neurofeedback (NF) to noninvasively alter patterns of brain connectivity, as measured by resting-state fMRI, and to reduce contamination anxiety. Activity of a region of the orbitofrontal cortex associated with contamination anxiety was measured in real time and provided to subjects with significant but subclinical anxiety as a NF signal, permitting them to learn to modulate the target brain region. NF altered network connectivity of brain regions involved in anxiety regulation: subjects exhibited reduced resting-state connectivity in limbic circuitry and increased connectivity in the dorsolateral prefrontal cortex. NF has been shown to alter brain connectivity in other contexts, but it has been unclear whether these changes persist; critically, we observed changes in connectivity several days after the completion of NF training, demonstrating that such training can lead to lasting modifications of brain functional architecture. Training also increased subjects' control over contamination anxiety several days after the completion of NF training. Changes in resting-state connectivity in the target orbitofrontal region correlated with these improvements in anxiety. Matched subjects undergoing a sham feedback control task showed neither a reorganization of resting-state functional connectivity nor an improvement in anxiety. These data suggest that NF can enable enhanced control over anxiety by persistently reorganizing relevant brain networks and thus support the potential of NF as a clinically useful therapy.

Tumour cell responses to new fibroblast growth factor receptor tyrosine kinase inhibitors and identification of a gatekeeper mutation in FGFR3 as a mechanism of acquired resistance

Fibroblast growth factor receptors (FGFRs) can act as driving oncoproteins in certain cancers, making them attractive drug targets. Here we have characterized tumour cell responses to two new inhibitors of FGFR1-3, AZ12908010 and the clinical candidate AZD4547, making comparisons with the well-characterized FGFR inhibitor PD173074. In a panel of 16 human tumour cell lines, the anti-proliferative activity of AZ12908010 or AZD4547 was strongly linked to the presence of deregulated FGFR signalling, indicating that addiction to deregulated FGFRs provides a therapeutic opportunity for selective intervention. Acquired resistance to targeted tyrosine kinase inhibitors is a growing problem in the clinic but has not yet been explored for FGFR inhibitors. To assess how FGFR-dependent tumour cells adapt to long-term FGFR inhibition, we generated a derivative of the KMS-11 myeloma cell line (FGFR(Y373C)) with acquired resistance to AZ12908010 (KMS-11R cells). Basal phosphorylated FGFR and FGFR-dependent downstream signalling were constitutively elevated and refractory to drug in KMS-11R cells. Sequencing of FGFR3 in KMS-11R cells revealed the presence of a heterozygous mutation at the gatekeeper residue, encoding FGFR3(V555M); consistent with this, KMS-11R cells were cross-resistant to AZD4547 and PD173074. These results define the selectivity and efficacy of two new FGFR inhibitors and identify a secondary gatekeeper mutation as a mechanism of acquired resistance to FGFR inhibitors that should be anticipated as clinical evaluation proceeds.

Transcranial magnetic stimulation and connectivity mapping: tools for studying the neural bases of brain disorders

There has been an increasing emphasis on characterizing pathophysiology underlying psychiatric and neurological disorders in terms of altered neural connectivity and network dynamics. Transcranial magnetic stimulation (TMS) provides a unique opportunity for investigating connectivity in the human brain. TMS allows researchers and clinicians to directly stimulate cortical regions accessible to electromagnetic coils positioned on the scalp. The induced activation can then propagate through long-range connections to other brain areas. Thus, by identifying distal regions activated during TMS, researchers can infer connectivity patterns in the healthy human brain and can examine how those patterns may be disrupted in patients with different brain disorders. Conversely, connectivity maps derived using neuroimaging methods can identify components of a dysfunctional network. Nodes in this dysfunctional network accessible as targets for TMS by virtue of their proximity to the scalp may then permit TMS-induced alterations of components of the network not directly accessible to TMS via propagated effects. Thus TMS can provide a portal for accessing and altering neural dynamics in networks that are widely distributed anatomically. Finally, when long-term modulation of network dynamics is induced by trains of repetitive TMS, changes in functional connectivity patterns can be studied in parallel with changes in patient symptoms. These correlational data can elucidate neural mechanisms underlying illness and recovery. In this review, we focus on the application of these approaches to the study of psychiatric and neurological illnesses.

Evaluation of the Basic Airway Model, a novel mask ventilation training manikin

The Basic Airway Model is an airway manikin designed for training in mask ventilation. We investigated the ability of the Basic Airway Model to provide varying levels of difficulty for mask ventilation. Volunteers with three levels of experience (novice, intermediate and expert) attempted to ventilate the manikin at three levels of difficulty: easy, intermediate and difficult. The distribution of frequencies of successful ventilation by different groups at the three levels of difficulty were statistically significant (p < 0.0001). The median (IQR (range)) degree of difficulty was 3 (2-5 (1-7)), 4 (3-5.3 (2-7)) and 6 (5-7 (3-9)) for easy, intermediate and difficult settings, respectively. We conclude that the Basic Airway Model can provide different levels of difficulty for mask ventilation training.

Cytogenetic and genetic evidence supports a role for the kainate-type glutamate receptor gene, GRIK4, in schizophrenia and bipolar disorder

In the search for the biological causes of schizophrenia and bipolar disorder, glutamate neurotransmission has emerged as one of a number of candidate processes and pathways where underlying gene deficits may be present. The analysis of chromosomal rearrangements in individuals diagnosed with neuropsychiatric disorders is an established route to candidate gene identification in both Mendelian and complex disorders. Here we describe a set of genes disrupted by, or proximal to, chromosomal breakpoints (2p12, 2q31.3, 2q21.2, 11q23.3 and 11q24.2) in a patient where chronic schizophrenia coexists with mild learning disability (US: mental retardation). Of these disrupted genes, the most promising candidate is a member of the kainate-type ionotropic glutamate receptor family, GRIK4 (KA1). A subsequent systematic case-control association study on GRIK4 assessed its contribution to psychiatric illness in the karyotypically normal population. This identified two discrete regions of disease risk within the GRIK4 locus: three single single nucleotide polymorphism (SNP) markers with a corresponding underlying haplotype associated with susceptibility to schizophrenia (P=0.0005, odds ratio (OR) of 1.453, 95% CI 1.182-1.787) and two single SNP markers and a haplotype associated with a protective effect against bipolar disorder (P=0.0002, OR of 0.624, 95% CI 0.485-0.802). After permutation analysis to correct for multiple testing, schizophrenia and bipolar disorder haplotypes remained significant (P=0.0430, s.e. 0.0064 and P=0.0190, s.e. 0.0043, respectively). We propose that these convergent cytogenetic and genetic findings provide molecular evidence for common aetiologies for different psychiatric conditions and further support the 'glutamate hypothesis' of psychotic illness.

Dopa decarboxylase genotypes may influence age at onset of schizophrenia

Several lines of evidence implicate dopa decarboxylase (DDC) with schizophrenia. By analysis of two putative functional DDC variants in 173 schizophrenic patients and 204 controls we tested the hypotheses that DDC is involved in: (1) predisposition to schizophrenia; and (2) modulation of age at disease onset. No association was observed with schizophrenia as a whole, whereas an association between DDC genotypes and age at disease onset was suggested in males (P = 0.03). This association was most pronounced in relation to genotypes of haplotypes comprising both variants, suggesting an additive model where one variant mediates early and the other late onset. Accordingly, the haplotype-based genotypes could be assigned into three groups by their possible relative effect on age at onset: an "early", "neutral" and "late" group. Dividing the male schizophrenics into four groups with increasing age at onset, the "early" genotypes were seen to decrease in frequency from 51.5% to 16.7% while the "late" genotypes increased from 12.1% to 33.3% (P = 0.02). The difference in mean age at onset between male patients with "early" genotypes vs patients with "late" genotypes was close to 5 years (95% CI: 0.7-8.8). Thus, DDC may possibly act as a modulator of age at onset in male schizophrenics.

The Alexander technique: its application in midwifery and the results of preliminary research into Parkinson's

This article outlines the origins and theory of the Alexander Technique and how it is learnt. Recent research is listed and a description given of main presenting symptoms and medical problems of pupils coming for lessons. The paper also describes how the Alexander Technique is used by women in pregnancy and childbirth and explains why it is beneficial. The final section describes Parkinson's research results, mainly from a preliminary study designed some years ago to test a methodology for a randomized controlled trial.

A theoretical investigation of reference frames for the planning of speech movements

Does the speech motor control system use invariant vocal tract shape targets when producing vowels and semivowels? A 4-part theoretical treatment favoring models whose only invariant targets are regions in auditory perceptual space over models that posit invariant constriction targets is presented. Auditory target regions are hypothesized to arise during development as an emergent property of neural map formation in the auditory system. Furthermore, speech movements are planned as trajectories in auditory perceptual space. These trajectories are then mapped into articulator movements through a neural mapping that allows motor equivalent variability in constriction locations and degrees when needed. These hypotheses are illustrated using computer simulations of the DIVA model of speech acquisition and production. Finally, several difficult challenges to proponents of constriction theories based on this theoretical treatment are posed.

The relationship between perimenstrual depressive mood and depressive illness

In a study of 144 women, mainly self-designated PMS sufferers, the premenstrual depression experienced was, apart from its shorter duration, quantitatively and qualitatively similar to major depressive disorder for a substantial proportion of subjects. The associations with previous history of depression were complex: the severity of premenstrual depression was related to previous history of postnatal depression, whereas its duration (i.e., whether it persisted through longer) was related to a history of treatment with antidepressants. Two independent dimensions are proposed. (i) A menstrual cycle-related factor which in vulnerable women can results in severe and disabling premenstrual dysphoria, and which may be aetiologically related to a subgroup of postnatal depression. (ii) In a minority of women a more general propensity for depressive illness evidence as a tendency for any premenstrual depression to be prolonged.

Should all pregnant women be screened for hepatitis B?

To assess the sensitivity of historical risk factors for identification for hepatitis B surface antigen (HBsAg)-positive parturients, 4399 pregnant women were consecutively screened for HBsAg. Information regarding risk for hepatitis B infection was obtained from each HBsAg-positive parturient. Twenty-three HBsAg-positive subjects were identified (5.2/1000 deliveries). The HBsAg carrier rate (18/2231, or 8.1/1000 deliveries) was significantly higher in women of black, Asian, or Hispanic origin than in the remaining ethnic groups (non-Hispanic whites plus all others, 5/2168, or 2.3/1000 deliveries) (chi square, 5.95; p = 0.016). Risk factors for identification of HBsAg-positive women were present in 10 of 22 asymptomatic subjects (sensitivity, 45%; 95% confidence interval, 24% to 68%). Much of the information required to assess one of these risk factors, previous infection, involved detailed questioning and is unlikely to be obtained in the context of conventional obstetrical care. Routine maternal HBsAg screening programs may be needed if transmission of hepatitis B from mother to infant is to be prevented.

Fluoxetine as a treatment for bulimia nervosa

The results of a small study using fluoxetine in the treatment of bulimia nervosa are presented. Ten subjects were treated on an open basis with fluoxetine 60-80 mg daily. Seven subjects stopped their bulimic behaviour completely, two improved and one was unchanged. The results indicate that fluoxetine may have a role in the treatment of bulimia and that further investigation is warranted. A brief review of other drug studies on bulimia nervosa is presented.