1
|
The influence of endogenous estrogen on high-frequency prefrontal transcranial magnetic stimulation. Brain Stimul 2019; 12:1271-1279. [DOI: 10.1016/j.brs.2019.05.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 04/03/2019] [Accepted: 05/06/2019] [Indexed: 01/06/2023] Open
|
2
|
Subgenual Functional Connectivity Predicts Antidepressant Treatment Response to Transcranial Magnetic Stimulation: Independent Validation and Evaluation of Personalization. Biol Psychiatry 2019; 86:e5-e7. [PMID: 30670304 DOI: 10.1016/j.biopsych.2018.12.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 12/04/2018] [Indexed: 01/12/2023]
|
3
|
Screening for depression with the Edinburgh Postnatal Depression Scale and finding borderline personality disorder. Aust N Z J Psychiatry 2019; 53:424-432. [PMID: 30309241 DOI: 10.1177/0004867418804067] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE The aim of the study was to explore the range of psychiatric diagnoses seen in pregnant women who score above the 'cut-off' on the Edinburgh Postnatal Depression Scale when this is used as a routine screening instrument in the antenatal period. METHOD Subjects were all pregnant women referred to and seen by the Perinatal Consultation-Liaison Psychiatry Team of a tertiary public hospital over a 14-month period. Edinburgh Postnatal Depression Scale score at maternity 'booking-in' visit, demographic and clinical data were recorded and diagnoses were made according to Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria following clinical interview(s) and review of documented past history. Data were analysed using descriptive statistics. RESULTS A total of 200 patients who had completed the Edinburgh Postnatal Depression Scale were seen for assessment; 86 (43%) scored ⩾13 on Edinburgh Postnatal Depression Scale. Of those scoring 13 or more on Edinburgh Postnatal Depression Scale, 22 (25.6%) had a depressive disorder. In total, 12 patients (14%) had an anxiety disorder, 14 (16.3%) had borderline personality disorder and 13 (15.1%) had a substance use disorder. An additional 23 women (26.7%) had two or more borderline personality traits. CONCLUSION Psychiatric assessment of women who scored 13 or more on the Edinburgh Postnatal Depression Scale at routine antenatal screening identified a significant number with borderline personality disorder or borderline personality traits rather than depressive or anxiety disorders. Clinical Practice Guidelines note the importance of further assessment for all women who score 13 or more on the Edinburgh Postnatal Depression Scale. The findings here suggest that this assessment should be made by a clinician able to identify personality pathology and organise appropriate and timely interventions.
Collapse
|
4
|
Differentiating responders and non-responders to rTMS treatment for depression after one week using resting EEG connectivity measures. J Affect Disord 2019; 242:68-79. [PMID: 30172227 DOI: 10.1016/j.jad.2018.08.058] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 07/30/2018] [Accepted: 08/12/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND Non-response to repetitive transcranial magnetic stimulation (rTMS) treatment for depression is costly for both patients and clinics. Simple and cheap methods to predict response would reduce this burden. Resting EEG measures differentiate responders from non-responders, so may have utility for response prediction. METHODS Fifty patients with treatment resistant depression and 21 controls had resting electroencephalography (EEG) recorded at baseline (BL). Patients underwent 5-8 weeks of rTMS treatment, with EEG recordings repeated at week 1 (W1). Forty-two participants had valid BL and W1 EEG data, and 12 were responders. Responders and non-responders were compared at BL and W1 in measures of theta (4-8 Hz) and alpha (8-13 Hz) power and connectivity, frontal theta cordance and alpha peak frequency. Control group comparisons were made for measures that differed between responders and non-responders. A machine learning algorithm assessed the potential to differentiate responders from non-responders using EEG measures in combination with change in depression scores from BL to W1. RESULTS Responders showed elevated theta connectivity across BL and W1. No other EEG measures differed between groups. Responders could be distinguished from non-responders with a mean sensitivity of 0.84 (p = 0.001) and specificity of 0.89 (p = 0.002) using cross-validated machine learning classification on the combination of all EEG and mood measures. LIMITATIONS The low response rate limited our sample size to only 12 responders. CONCLUSION Resting theta connectivity at BL and W1 differ between responders and non-responders, and show potential for predicting response to rTMS treatment for depression.
Collapse
|
5
|
The influence of endogenous estrogen on transcranial direct current stimulation: A preliminary study. Eur J Neurosci 2018; 48:2001-2012. [PMID: 30044024 DOI: 10.1111/ejn.14085] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 07/08/2018] [Accepted: 07/10/2018] [Indexed: 02/06/2023]
Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulatory technique. Responses to tDCS differ substantially between individuals. Sex hormones that modulate cortical excitability, such as estrogen, may contribute to this inter-individual variability. The influence of estrogen on tDCS after-effects has not yet been researched. This study aimed to investigate whether endogenous estrogen levels influence cortical response to tDCS. Data from 15 male and 14 female healthy adults were analyzed. Males completed one experimental session. Females completed two, one during the early follicular phase of the menstrual cycle when estrogen was low, one during the mid-luteal phase when estrogen was high. Each session comprised 15-min of anodal tDCS delivered to the left dorsolateral prefrontal cortex (DLPFC). Response to stimulation was assessed using electroencephalography with DLPFC transcranial magnetic stimulation (TMS) administered before, immediately after, and 20-min after tDCS. Changes in amplitudes of N120 and P200 components of TMS-evoked potentials over time were compared between males, women with low estrogen and women with high estrogen. Blood assays verified estrogen levels. Women with high estrogen demonstrated a significant increase in P200 amplitude at both time points and change over time was greater for the high estrogen group compared with males. No significant differences were observed between males and women with low estrogen, or between women with low and high estrogen. These preliminary results indicate that greater neuroplastic response to DLPFC tDCS is seen in highest compared with lowest estrogen states, suggesting that endogenous estrogen levels contribute to inter-individual variability of tDCS outcomes.
Collapse
|
6
|
Electroconvulsive therapy (ECT) during pregnancy: quantifying and assessing the electric field strength inside the foetal brain. Sci Rep 2018; 8:4128. [PMID: 29515221 PMCID: PMC5841342 DOI: 10.1038/s41598-018-22528-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 02/26/2018] [Indexed: 11/12/2022] Open
Abstract
Electroconvulsive therapy (ECT) is an effective treatment option for severe mental illness during pregnancy. However, there is little knowledge about the amount of electric field produced inside the foetus, which is important to understand the effects of ECT on the foetal excitable tissues. Thus, in this paper, the electric field strength inside the foetus was computed and compared to the basic restriction of the International Commission for Non-Ionizing Radiation Protection (ICNIRP). A computational human phantom representing a 30-weeks pregnant female, four types of electrode placements and a range of stimulus pulse width (0.25 ms-2 ms) and frequency (10 Hz-140 Hz) were used to compute the electric field inside the foetus. A linear relationship between the maximum electric field inside the foetal brain and the electrode current was derived. The results suggest that, considering the maximum current output, pulse width, and frequency range of constant-current ECT devices, the electric field produced inside the foetal brain is most likely below the ICNIRP basic restriction. This is based on the practical scenario of a 30-weeks foetus with a bottom-up and head-down foetal position and the mother taller than 1.62 m.
Collapse
|
7
|
Responders to rTMS for depression show increased fronto-midline theta and theta connectivity compared to non-responders. Brain Stimul 2018; 11:190-203. [PMID: 29128490 DOI: 10.1016/j.brs.2017.10.015] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 10/11/2017] [Accepted: 10/15/2017] [Indexed: 02/01/2023] Open
|
8
|
Demonstration of short-term plasticity in the dorsolateral prefrontal cortex with theta burst stimulation: A TMS-EEG study. Clin Neurophysiol 2017; 128:1117-1126. [DOI: 10.1016/j.clinph.2017.04.005] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 03/28/2017] [Accepted: 04/04/2017] [Indexed: 12/13/2022]
|
9
|
Abstract
OBJECTIVE To investigate the prevalence of occipital bending (an occipital lobe crossing or twisting across the midline) in subjects with schizophrenia and matched healthy controls. METHOD Occipital bending prevalence was investigated in 37 patients with schizophrenia and 44 healthy controls. RESULTS Ratings showed that prevalence was nearly three times higher among schizophrenia patients (13/37 [35.1%]) than in control subjects (6/44 [13.6%]). Furthermore, those with schizophrenia had greater normalized gray matter volume but less white matter volume and had larger brain-to-cranial ratio. CONCLUSION The results suggest that occipital bending is more prevalent among schizophrenia patients than healthy subjects and that schizophrenia patients have different gray matter-white matter proportions. Although the cause and clinical ramifications of occipital bending are unclear, the results infer that occipital bending may be a marker of psychiatric illness.
Collapse
|
10
|
Brain morphometry in blind and sighted subjects. J Clin Neurosci 2016; 33:89-95. [DOI: 10.1016/j.jocn.2016.01.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 01/04/2016] [Accepted: 01/17/2016] [Indexed: 10/21/2022]
|
11
|
Analysing concurrent transcranial magnetic stimulation and electroencephalographic data: A review and introduction to the open-source TESA software. Neuroimage 2016; 147:934-951. [PMID: 27771347 DOI: 10.1016/j.neuroimage.2016.10.031] [Citation(s) in RCA: 177] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 09/16/2016] [Accepted: 10/18/2016] [Indexed: 11/16/2022] Open
Abstract
The concurrent use of transcranial magnetic stimulation with electroencephalography (TMS-EEG) is growing in popularity as a method for assessing various cortical properties such as excitability, oscillations and connectivity. However, this combination of methods is technically challenging, resulting in artifacts both during recording and following typical EEG analysis methods, which can distort the underlying neural signal. In this article, we review the causes of artifacts in EEG recordings resulting from TMS, as well as artifacts introduced during analysis (e.g. as the result of filtering over high-frequency, large amplitude artifacts). We then discuss methods for removing artifacts, and ways of designing pipelines to minimise analysis-related artifacts. Finally, we introduce the TMS-EEG signal analyser (TESA), an open-source extension for EEGLAB, which includes functions that are specific for TMS-EEG analysis, such as removing and interpolating the TMS pulse artifact, removing and minimising TMS-evoked muscle activity, and analysing TMS-evoked potentials. The aims of TESA are to provide users with easy access to current TMS-EEG analysis methods and to encourage direct comparisons of these methods and pipelines. It is hoped that providing open-source functions will aid in both improving and standardising analysis across the field of TMS-EEG research.
Collapse
|
12
|
Abstract
The modulation of brain function via the application of weak direct current was first observed directly in the early 19th century. In the past 3 decades, transcranial magnetic stimulation and deep brain stimulation have undergone clinical translation, offering alternatives to pharmacological treatment of neurological and neuropsychiatric disorders. Further development of novel neuromodulation techniques employing ultrasound, micro-scale magnetic fields and optogenetics is being propelled by a rapidly improving understanding of the clinical and experimental applications of artificially stimulating or depressing brain activity in human health and disease. With the current rapid growth in neuromodulation technologies and applications, it is timely to review the genesis of the field and the current state of the art in this area.
Collapse
|
13
|
No evidence for mirror system dysfunction in schizophrenia from a multimodal TMS/EEG study. Psychiatry Res 2015; 228:431-40. [PMID: 26154818 DOI: 10.1016/j.psychres.2015.05.067] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 05/20/2015] [Accepted: 05/25/2015] [Indexed: 11/26/2022]
Abstract
Dysfunctional mirror neuron systems have been proposed to contribute to the social cognitive deficits observed in schizophrenia. A few studies have explored mirror systems in schizophrenia using various techniques such as TMS (levels of motor resonance) or EEG (levels of mu suppression), with mixed results. This study aimed to use a novel multimodal approach (i.e. concurrent TMS and EEG) to further investigate mirror systems and social cognition in schizophrenia. Nineteen individuals with schizophrenia or schizoaffective disorder and 19 healthy controls participated. Single-pulse TMS was applied to M1 during the observation of hand movements designed to elicit mirror system activity. Single EEG electrodes (C3, CZ, C4) recorded brain activity. Participants also completed facial affect recognition and theory of mind tasks. The schizophrenia group showed significant deficits in facial affect recognition and higher level theory of mind compared to healthy controls. A significant positive relationship was revealed between mu suppression and motor resonance for the overall sample, indicating concurrent validity of these measures. Levels of mu suppression and motor resonance were not significantly different between groups. These findings indicate that in stable outpatients with schizophrenia, mirror system functioning is intact, and therefore their social cognitive difficulties may be caused by alternative pathophysiology.
Collapse
|
14
|
Reduced mu suppression and altered motor resonance in euthymic bipolar disorder: Evidence for a dysfunctional mirror system? Soc Neurosci 2015; 11:60-71. [DOI: 10.1080/17470919.2015.1029140] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
15
|
A near infra-red study of blood oxygenation changes resulting from high and low frequency repetitive transcranial magnetic stimulation. Brain Stimul 2015. [DOI: 10.1016/j.brs.2015.01.171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
16
|
Volumetric, cortical thickness and white matter integrity alterations in bipolar disorder type I and II. J Affect Disord 2014; 169:118-27. [PMID: 25189991 DOI: 10.1016/j.jad.2014.08.016] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/25/2014] [Accepted: 08/10/2014] [Indexed: 01/07/2023]
Abstract
BACKGROUND Bipolar disorder (BD) is a debilitating psychiatric disorder affecting millions of people worldwide with mean time to diagnosis estimated to be at least 10 years. Whilst many brain imaging studies have compared those with BD to controls, few have attempted to investigate differences between BD Type I and II and matched controls. METHODS Thirty-one patients with BD (16 Type I and 15 Type II) and 31 matched healthy controls were MRI brain scanned with conventional T1-weighted and diffusion tensor imaging methods. RESULTS There was significantly reduced regional brain volume and thickness among the BD subjects, but also between BD Type I when compared to Type II. White matter integrity also differed between the groups and BD severity correlated significantly with regional brain volume and thickness. LIMITATIONS Future investigations will consider length of time each BD patient had been diagnosed with BD, as well as assessing controls for family history of psychiatric illness, specifically BD. Similarly, genetic assessment will be conducted as well. CONCLUSIONS These findings suggest that there are not only regional brain volumetric, thickness and white matter integrity differences between BD and matched controls, but also between those with BD Type I and Type II, such that reduced regional brain volume may underlie BD Type I whereas white matter integrity is more altered in BD Type II.
Collapse
|
17
|
Removing artefacts from TMS-EEG recordings using independent component analysis: Importance for assessing prefrontal and motor cortex network properties. Neuroimage 2014; 101:425-39. [DOI: 10.1016/j.neuroimage.2014.07.037] [Citation(s) in RCA: 186] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 06/19/2014] [Accepted: 07/17/2014] [Indexed: 11/30/2022] Open
|
18
|
Testing the limits: Investigating the effect of tDCS dose on working memory enhancement in healthy controls. Neuropsychologia 2013; 51:1777-84. [DOI: 10.1016/j.neuropsychologia.2013.05.018] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 05/17/2013] [Accepted: 05/24/2013] [Indexed: 11/30/2022]
|
19
|
Short-latency artifacts associated with concurrent TMS-EEG. Brain Stimul 2013; 6:868-76. [PMID: 23651674 DOI: 10.1016/j.brs.2013.04.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 04/03/2013] [Accepted: 04/10/2013] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Concurrent transcranial magnetic stimulation and electroencephalography (TMS-EEG) is an emerging method for studying cortical network properties. However, various artifacts affect measurement of TMS-evoked cortical potentials (TEPs), especially within 30 ms of stimulation. OBJECTIVE/HYPOTHESIS The aim of this study was to assess the origin and recovery of short-latency TMS-EEG artifacts (<30 ms) using different stimulators and under different experimental conditions. METHODS EEG was recorded during TMS delivered to a phantom head (melon) and 12 healthy volunteers with different TMS machines, at different scalp positions, at different TMS intensities, and following paired-pulse TMS. Recovery from the TMS artifact and other short-latency artifacts were compared between conditions. RESULTS Following phantom stimulation, the artifact resulting from different TMS machines (Magstim 200, Magventure MagPro R30 and X100) and pulse shapes (monophasic and biphasic) resulted in different artifact profiles. After accounting for differences between machines, TMS artifacts recovered within ∼12 ms. This was replicated in human participants, however a large secondary artifact (peaks at 5 and 10 ms) became prominent following stimulation over lateral scalp positions, which only recovered after ∼25-40 ms. Increasing TMS intensity increased secondary artifact amplitude over both motor and prefrontal cortex. There was no consistent modulation of the secondary artifact following inhibitory paired-pulse TMS (interstimulus interval = 100 ms) over motor cortex. CONCLUSIONS The secondary artifact observed in humans is consistent with activation of scalp muscles following TMS. TEPs can be recorded within a short period of time (10-12 ms) following TMS, however measures must be taken to avoid muscle stimulation.
Collapse
|
20
|
Effect of magnetic seizure therapy on regional brain glucose metabolism in major depression. Psychiatry Res 2013; 211:169-75. [PMID: 23149039 DOI: 10.1016/j.pscychresns.2012.08.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 08/02/2012] [Accepted: 08/06/2012] [Indexed: 11/30/2022]
Abstract
Currently electroconvulsive therapy (ECT) is one of the only available therapies for treatment resistant depression (TRD). While effective, ECT is complicated by side effects, including cognitive impairment. One promising potential alternative is magnetic seizure therapy (MST). To date, no research has explored the effects of 100Hz MST on brain activity or the brain changes associated with response to treatment. Therefore the aim of this study was to determine the effects of a treatment course of 100Hz MST on regional brain glucose metabolism. Ten patients with treatment resistant depression underwent positron emission tomography with fluorodeoxyglucose before and after a treatment course of MST. Changes in the relative metabolic rate of a priori brain regions were investigated. Areas of increased relative metabolism after treatment were seen in the basal ganglia, orbitofrontal cortex, medial frontal cortex and dorsolateral prefrontal cortex. A secondary analysis showed trend-level differential findings in brain activation between responders and non-responders, namely in the ventral anterior cingulate. These results primarily indicate that MST is affecting regions consistent with the limbic-cortical dysregulation model of depression. Exploratory analysis indicated some differential findings in brain activation between responders and non-responders were also evident; however, the small sample size precludes any firm conclusions.
Collapse
|
21
|
Emotive interference during cognitive processing in major depression: an investigation of lower alpha 1 activity. J Affect Disord 2012; 141:185-93. [PMID: 22534463 DOI: 10.1016/j.jad.2012.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 03/05/2012] [Accepted: 03/05/2012] [Indexed: 11/16/2022]
Abstract
BACKGROUND Individuals with Major Depressive Disorder (MDD) tend to be more susceptible to distraction by negative emotional material than their non-depressed counterparts. This extends to an enhanced vulnerability to interference from mood-congruent stimuli during cognitive processing. The current study investigated the electrophysiological correlates of competing cognitive and emotional processing demands in MDD. METHODS Event-related alpha activity within the lower alpha 1 band was examined during the online information retention phase of a non-emotive WM task with extraneous emotional stimuli (positive, negative and neutral) presented as background images. EEG activity over posterior parietal cortex was compared between 15 acutely depressed and 16 never depressed right-handed women. RESULTS A valence specific dissociation in lower alpha 1 activity was observed between the two groups, consistent with greater attentional resource allocation to positive distracters in control participants and to negative distracters in MDD participants. No group differences were seen when neutral distracters were displayed. CONCLUSIONS These results demonstrate that activity within the lower alpha 1 band is sensitive to competing emotional and cognitive processing demands and highlight the importance of posterior parietal regions in depression-related susceptibility to affective distractibility during cognitive processing.
Collapse
|
22
|
Individual Differences in Moral Behaviour: A Role for Response to Risk and Uncertainty? NEUROETHICS-NETH 2012. [DOI: 10.1007/s12152-012-9158-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
23
|
Blood oxygenation changes resulting from trains of low frequency transcranial magnetic stimulation. Cortex 2012; 48:487-91. [DOI: 10.1016/j.cortex.2011.04.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 11/04/2010] [Accepted: 04/20/2011] [Indexed: 11/28/2022]
|
24
|
Atypical electrophysiological activity during pain observation in amputees who experience synaesthetic pain. Soc Cogn Affect Neurosci 2012; 7:357-68. [PMID: 21565941 PMCID: PMC3304487 DOI: 10.1093/scan/nsr016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 02/24/2011] [Indexed: 12/24/2022] Open
Abstract
There are increasing reports of people experiencing pain when observing pain in another. This describes the phenomenon of synaesthetic pain which, until recently, had been primarily reported in amputees with phantom pain. In the current study, we used electroencephalography (EEG) to investigate how amputees who experience synaesthetic pain process pain observed in another. Participants were grouped according to amputees who experience phantom and synaesthetic pain (n=8), amputees who experience phantom pain but not synaesthetic pain (n=10) and healthy controls (n=10). Participants underwent EEG as they observed still images of hands and feet in potentially painful and non-painful situations. We found that pain synaesthetes showed some reduced event-related potential (ERP) components at certain electrode sites, and reduced theta- and alpha band power amplitude at a central electrode. The finding of reduced ERP amplitude and theta band power may reflect inhibition of the processing of observed pain (e.g. avoidance/guarding as a protective strategy), and reduced alpha band power may indicate a disinhibition in control processes that may result in synaesthetic pain. These results provide the first documentation of atypical neurophysiological activity in amputees who experience synaesthetic pain when processing pain in another.
Collapse
|
25
|
Blood oxygenation changes resulting from suprathreshold transcranial magnetic stimulation. Brain Stimul 2011; 4:165-8. [DOI: 10.1016/j.brs.2010.10.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2010] [Revised: 10/15/2010] [Accepted: 10/19/2010] [Indexed: 10/18/2022] Open
|
26
|
A near infra-red spectroscopy study of the effects of pre-frontal single and paired pulse transcranial magnetic stimulation. Clin Neurophysiol 2011; 122:378-82. [PMID: 20817548 DOI: 10.1016/j.clinph.2010.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 08/05/2010] [Accepted: 08/06/2010] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Concentration changes in hemoglobin following single and paired pulse (2 and 15 ms inter-stimulus interval) transcranial magnetic stimulation (TMS) was investigated using near infra-red spectroscopy (NIRS). METHODS TMS was delivered to left pre-frontal cortex at typical intensities used in neuroscience research and concentrations of deoxyhemoglobin (Hb), oxyhemoglobin (HbO) and total hemoglobin (HbT) were measured. RESULTS Significant drops in concentration of HbO and HbT were observed and while there was no effect of the different pulse types on amplitude, there was a difference in the time taken to return to baseline. CONCLUSIONS The changes observed imply that in pre-frontal cortex, the different TMS pulse types result in differential effects on oxygen consumption. SIGNIFICANCE This study aids our understanding of the physiological effects of single and paired pulse TMS.
Collapse
|
27
|
Abstract
Lateralized differences in frontal alpha power in individuals with major depressive disorder (MDD) are thought to reflect an aberrant affective processing style. However research into anterior alpha asymmetry and MDD has often produced conflicting results. The current study aimed to investigate whether individualized alpha bandwidths provide a more sensitive measure of anterior alpha asymmetry in MDD than the traditional fixed 8-13 Hz alpha band. Resting EEG was recorded from 34 right-handed female participants (18 controls, 16 MDD). Each participant's Individual Alpha Frequency was used to delineate a broad individualized alpha band and three individualized narrow alpha sub-bands: lower alpha1, lower alpha 2 and upper alpha. Activity within the broad and narrow individualized bandwidths and within the traditional fixed alpha band were used to compare a) controls and acutely depressed individuals and b) medicated and unmedicated MDD participants. Individualizing and subdividing the alpha bandwidth did not add appreciably to the sensitivity of anterior alpha asymmetry in MDD as no significant differences in lateralized alpha power between controls and MDD participants were observed in any alpha bandwidth. This finding was consistent under two reference schemes and across multiple scalp locations. Within the MDD group, antidepressant use was associated with significantly greater right than left hemispheric power in the lower alpha 1 band. The relevance of this finding is discussed in relation to the electrophysiological correlates of antidepressant medication use, lateralized differences in affective processing and treatment resistant MDD.
Collapse
|
28
|
Upper alpha activity during working memory processing reflects abnormal inhibition in major depression. J Affect Disord 2010; 127:191-8. [PMID: 20579742 DOI: 10.1016/j.jad.2010.05.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 05/24/2010] [Accepted: 05/29/2010] [Indexed: 11/30/2022]
Abstract
BACKGROUND EEG studies examining 'resting' state (i.e. non-task) state brain activity in major depressive disorder (MDD) have reported numerous abnormalities within the alpha bandwidth. These findings are discussed extensively within affective disorders literature but their relationship to functional aspects of depressive psychopathology remains unclear. Investigating alpha modulation during active cognitive processing may provide a more targeted means of relating aberrant alpha activity to specific aspects of depression symptomatology. Alpha activity is reliably modulated during working memory (WM) processing and WM impairments are a common neuropsychological consequence of MDD. Moreover, it has been suggested that alpha activity reflects internally mediated inhibitory process and attenuated inhibition has been suggested to contribute to WM inefficacy. AIM The current investigation examined whether alpha was modulated differently in MDD participants during WM processing and whether the pattern of alpha activity was consistent with impairments in inhibitory processes. METHOD Event related synchronisation (ERS) within the upper alpha band over the retention interval of a modified Sternberg WM task was examined in 15 acutely depressed and 15 never depressed right-handed female participants. RESULTS MDD participants displayed greater upper alpha ERS than controls during the online information maintenance component of WM processing. This was evident over left, but not right, parieto-occipital cortex. CONCLUSION The results are consistent with increased inhibition of extraneous material during WM processing in depression. This may reflect a neurobiological compensation strategy whereby additional neural resources are required to achieve comparable performance accuracy during effortful cognitive processing in MDD.
Collapse
|
29
|
Distribution of naturally occurring quinones. PHARMACEUTISCH WEEKBLAD. SCIENTIFIC EDITION 1991; 13:70-3. [PMID: 1870945 DOI: 10.1007/bf01974983] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Angiosperms, fungi (including lichens), and bacteria are the main sources of natural quinones. Small numbers are present in algae, ferns, conifers, sponges, echinoderms, other marine animals, and arthropods. In angiosperms quinones have some chemotaxonomic value at the genus and family level but more surveys are required.
Collapse
|
30
|
5,8-dihydroxyflavone (primetin) the contact sensitizer of Primula mistassinica Michaux. Arch Dermatol Res 1983; 275:365-70. [PMID: 6660907 DOI: 10.1007/bf00417334] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
5,8-Dihydroxyflavone (primetin) has been shown to be the sensitizer in Primula mistassinica Michaux and probably the source of allergic contact dermatitis in four milkers. Its sensitizing properties as determined in guinea-pigs, are strong. As far as is known this is the first experimental demonstration of the sensitizing potency of a flavone. Presumably the flavone, with its uncommon 5,8-arrangement of hydroxy groups, is oxidized in the skin to the corresponding quinone (primetinquinone). Quinone was prepared from primetin and used for experimental sensitization of guinea-pigs. It also revealed strong sensitizing properties. Cross-reactions were obtained not only with the synthetic quinone in the flavone-sensitive animals but also with primetin in primetinquinone-sensitive guinea-pigs. Preliminary sensitization tests with other flavones have demonstrated that the whole group of flavonoid components should be taken into consideration as potential sensitizers.
Collapse
|
31
|
Factors affecting the survival of Salmonella and Escherichia coli in anaerobically fermented pig waste. THE JOURNAL OF APPLIED BACTERIOLOGY 1983; 55:89-95. [PMID: 6352597 DOI: 10.1111/j.1365-2672.1983.tb02651.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The survival of Salmonella typhimurium was investigated in acidogenic, anaerobically fermented pig wastes and in synthetic media, each containing volatile fatty acids (VFA). Salm. typhimurium survived at pH 6.8, but not at pH 4.0, when incubated at 37 degrees C for 24 h in either fermented or synthetic medium containing VFA. The minimum inhibiting concentration of VFA for Salm. typhimurium after 48 h incubation at 30 degrees C at pH 4.0 was 0.03 mol/l and for Escherichia coli it was 0.09 mol/l. Fermented pig wastes in a digester, maintained at pH 5.9, were inoculated with Salm. typhimurium and then incubated at 37 degrees C for 24 h. The pH was adjusted to either 4.0 or 5.0 and after a further 48 h at 30 degrees C, Salm. typhimurium survived at pH 5.0 but not at pH 4.0. It was concluded that pH is critical in determining the survival of this organism in acidogenic anaerobically fermented pig waste.
Collapse
|
32
|
Gadusol, an enolic derivative of cyclohexane-1,3-dione present in the roes of cod and other marine fish. Isolation, properties and occurrence compared with ascorbic acid. Biochem J 1981; 199:741-7. [PMID: 7200360 PMCID: PMC1163432 DOI: 10.1042/bj1990741] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Gadusol, C8H12O6, has been isolated from roes of the cod (Gadus morhua L.), i.e., ovaries that contain ripe eggs just before spawning. The concentration is about 4 g/kg dry wt. It has been identified as 1,4,5-trihydroxy-5-hydroxymethyl-2-methoxycyclo-hex-1-en-3-one and this structure was confirmed by synthesis of the anhydro tetra-acetate derivative from methyl 3,5-diacetoxy-4-methoxybenzoate. Concentrations of gadusol in the roes of other marine teleost fish examined are of the same order as in cod roes. Gadusol has some properties similar to ascorbic acid and both compounds, after oxidation, react with 2,4-dinitrophenylhydrazine in the commonly-used assay procedure for ascorbic acid. Specific assays showed that the concentrations of gadusol in the roes of marine fish are severalfold greater than those of ascorbic acid. Gadusol is structurally related to the mycosporines previously reported from a number of different organisms.
Collapse
|
33
|
Growth of
Candida ingens
on Supernatant from Anaerobically Fermented Pig Waste: Effects of Temperature and pH. Appl Environ Microbiol 1979; 37:1132-6. [PMID: 16345395 PMCID: PMC243367 DOI: 10.1128/aem.37.6.1132-1136.1979] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Candida ingens
, a pellicle-forming yeast utilizing volatile fatty acids, grew over a pH range of 4.1 to 6.0 on nonsterile supernatants from anaerobically fermented pig wastes; growth was inconsistent between pH 4.1 and 4.6. When ambient temperature above the pellicle was 21°C and the temperature of the medium was 29 to 32°C, a pH range of 4.8 to 5.0 gave yields of 1.90 to 3.31 g of dry matter per liter, and 0.059 to 0.065 mol of volatile fatty acids was utilized per liter. There was no advantage in utilization of volatile fatty acids and yield of dry matter in keeping the pH constant during a 24-h growth period.
C. ingens
grew at pH 4.8 and 5.0 when both ambient and medium temperatures were 30°C. When ambient temperature was 10°C, maximum yield and utilization of volatile fatty acids occurred at a medium temperature of 28 to 30°C.
Collapse
|
34
|
Efficiency of protein production from yeast grown in liquor derived from anaerobically fermented tropical pasture. Nature 1978; 274:619-20. [PMID: 27726 DOI: 10.1038/274619a0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
35
|
Study of Candida ingens grown on the supernatant derived from the anaerobic fermentation of monogastric animal wastes. Appl Environ Microbiol 1976; 31:813-8. [PMID: 945718 PMCID: PMC169839 DOI: 10.1128/aem.31.6.813-818.1976] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A pellicle-forming yeast, identified as Candida ingens, was found to grow on substrates derived from the anerobic fermentation of monogastric animal wastes. The organism used volatile fatty acids C2 to C6 and ammonia nitrogen. It had a preferential uptake of the acids in increasing order of molecular weight, removing 90% of the total titratable volatile acid. The nonwrinkled pellicle had a doubling time of 3.2 h, and the doubling time of the wrinkled pellicle was 4.2 h. Proximate amino acid and nucleic acid analyses suggested that the organism might be acceptable as a source of single cell protein. Its vitamin B group content compared favorably with that of other yeasts. It contained 6% calcium and 7% phosphorus. It could be useful in removing these minerals from effluents as well as in providing them as nutrients in livestock rations.
Collapse
|
36
|
|
37
|
Mode of action of carcinogenic amines. I. Oxidation of N-arylhydroxamic acids. JOURNAL OF THE CHEMICAL SOCIETY. PERKIN TRANSACTIONS 1 1970; 8:1081-3. [PMID: 5464278 DOI: 10.1039/j39700001081] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
38
|
|
39
|
Lapachol. Chem Ind 1968; 50:1771. [PMID: 5728162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|