An fMRI Study Examining Effects of Acute D-Cycloserine During Symptom Provocation in Spider Phobia

CNS Spectrums ◽  
2009 ◽  
Vol 14 (10) ◽  
pp. 556-571 ◽  
Author(s):  
Robin L. Aupperle ◽  
Lisa R. Hale ◽  
Rebecca J. Chambers ◽  
Sharon E. Cain ◽  
Frank X. Barth ◽  
...  

ABSTRACTBackground: Exposure-based therapy for anxiety disorders is believed to operate on the basis of fear extinction. Studies have shown acute administration of D-cycloserine (DCS) enhances fear extinction in animals and facilitates exposure therapy in humans, but the neural mechanisms are not completely understood. To date, no study has examined neural effects of acute DCS in anxiety-disordered populations.Methods: Two hours prior to functional magnetic resonance imaging scanning, 23 spider-phobic and 23 non-phobic participants were randomized to receive DCS 100 mg or placebo. During scanning, participants viewed spider, butterfly, and Gaussian-blurred baseline images in a block-design paradigm. Diagnostic and treatment groups were compared regarding differential activations to spider versus butterfly stimuli.Results: In the phobic group, DCS enhanced prefrontal (PFC), dorsal anterior cingulate (ACC), and insula activations. For controls, DCS enhanced ventral ACC and caudate activations. There was a positive correlation between lateral PFC and amygdala activation for the placebo-phobic group. Reported distress during symptom provocation was correlated with amygdala activation in the placebo-phobic group and orbitofrontal cortex activation in the DCS-phobic group.Conclusions: Results suggest that during initial phobic symptom provocation DCS enhances activation in regions involved in cognitive control and interoceptive integration, including the PFC, ACC, and insular cortices for phobic participants.

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Kevin Hilbert ◽  
Ricarda Evens ◽  
Nina Isabel Maslowski ◽  
Hans-Ulrich Wittchen ◽  
Ulrike Lueken

While previous studies successfully identified the core neural substrates of the animal subtype of specific phobia, only few and inconsistent research is available for dental phobia. These findings might partly relate to the fact that, typically, visual stimuli were employed. The current study aimed to investigate the influence of stimulus modality on neural fear processing in dental phobia. Thirteen dental phobics (DP) and thirteen healthy controls (HC) attended a block-design functional magnetic resonance imaging (fMRI) symptom provocation paradigm encompassing both visual and auditory stimuli. Drill sounds and matched neutral sinus tones served as auditory stimuli and dentist scenes and matched neutral videos as visual stimuli. Group comparisons showed increased activation in the insula, anterior cingulate cortex, orbitofrontal cortex, and thalamus in DP compared to HC during auditory but not visual stimulation. On the contrary, no differential autonomic reactions were observed in DP. Present results are largely comparable to brain areas identified in animal phobia, but also point towards a potential downregulation of autonomic outflow by neural fear circuits in this disorder. Findings enlarge our knowledge about neural correlates of dental phobia and may help to understand the neural underpinnings of the clinical and physiological characteristics of the disorder.


2010 ◽  
Vol 41 (4) ◽  
pp. 789-798 ◽  
Author(s):  
C. Sehlmeyer ◽  
U. Dannlowski ◽  
S. Schöning ◽  
H. Kugel ◽  
M. Pyka ◽  
...  

BackgroundFear conditioning involves the amygdala as the main neural structure for learning fear responses whereas fear extinction mainly activates the inhibitory prefrontal cortex (PFC). In this study we investigated whether individual differences in trait anxiety affect amygdala and dorsal anterior cingulate cortex (dACC) activation during fear conditioning and extinction.MethodThirty-two healthy subjects were investigated by functional magnetic resonance imaging (fMRI) at 3 T while performing a cued fear-conditioning task. All participants completed the trait version of the State-Trait Anxiety Inventory (STAI-T). Activations of the amygdala and the dACC were examined with respect to the effects of trait anxiety.ResultsAnalysis of the fMRI data demonstrated enhanced activation in fear-related brain areas, such as the insula and the ACC, during both fear conditioning and extinction. Activation of the amygdala appeared only during the late acquisition phase whereas deactivation was observed during extinction. Regression analyses revealed that highly trait-anxious subjects exhibited sustained amygdala activation and reduced dACC involvement during the extinction of conditioned responses.ConclusionsThis study reveals that high levels of trait anxiety are associated with both increased amygdala activation and reduced dACC recruitment during the extinction of conditioned fear. This hyper-responsitivity of the amygdala and the deficient cognitive control during the extinction of conditioned fear in anxious subjects reflect an increased resistance to extinct fear responses and may thereby enhance the vulnerability to developing anxiety disorders.


2007 ◽  
Vol 40 (05) ◽  
Author(s):  
N Chechko ◽  
M Czisch ◽  
A Erhardt ◽  
D Hoehn ◽  
R Wehrle ◽  
...  

2021 ◽  
Vol 7 (15) ◽  
pp. eabf6780
Author(s):  
Corinde E. Wiers ◽  
Leandro F. Vendruscolo ◽  
Jan-Willem van der Veen ◽  
Peter Manza ◽  
Ehsan Shokri-Kojori ◽  
...  

Individuals with alcohol use disorder (AUD) show elevated brain metabolism of acetate at the expense of glucose. We hypothesized that a shift in energy substrates during withdrawal may contribute to withdrawal severity and neurotoxicity in AUD and that a ketogenic diet (KD) may mitigate these effects. We found that inpatients with AUD randomized to receive KD (n = 19) required fewer benzodiazepines during the first week of detoxification, in comparison to those receiving a standard American (SA) diet (n = 14). Over a 3-week treatment, KD compared to SA showed lower “wanting” and increased dorsal anterior cingulate cortex (dACC) reactivity to alcohol cues and altered dACC bioenergetics (i.e., elevated ketones and glutamate and lower neuroinflammatory markers). In a rat model of alcohol dependence, a history of KD reduced alcohol consumption. We provide clinical and preclinical evidence for beneficial effects of KD on managing alcohol withdrawal and on reducing alcohol drinking.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 347-348
Author(s):  
Kelsey Schubach ◽  
Bruno I Cappellozza ◽  
Marcos Renato Burim ◽  
André Velasco ◽  
Fernando Sagrado ◽  
...  

Abstract Alternatives that alleviate stress-related responses and improve performance of the beef cattle herd are imperative and deserve further investigation. In previous trials, administration of the bovine appeasing substance (BAS) has improved performance of newly-weaned and feedlot received beef animals, as well as reduced the risk of dark, firm, and dry (DFD) cuts in carcass obtained from Bos indicus cattle. Therefore, this study was designed to evaluate the effects of BAS administration at castration on pre-conditioning performance of crossbred beef animals. On day 0, 390 crossbred Angus × Nellore animals were ranked by initial shrunk BW (255 ± 21.1 kg) and assigned to receive or not (CON) 5 mL/head of BAS (SecureCattle; Nutricorp, Araras, SP, Brazil) immediately before castration. From d 0 to 30, animals within treatments were maintained in 2 feedot pens with a minimum distance (300 m) to avoid contact between treatment groups and received a grass hay-based diet (70:30 roughage:concentrate ratio) ad libitum. On day 30, animals were individually weighed following 16 hours of feed and water restriction. Hence, a descriptive analysis was performed to evaluate pen dry matter intake (DMI) and feed efficiency (FE). Animal was considered the experimental unit and all data were analyzed using the PROC MIXED procedure of SAS (version 9.4; SAS Inst. Inc., Cary, NC). Bovine appeasing substance administration at castration improved ADG and BW change (P < 0.0001) compared with CON cohorts (0.983 vs. 1.155 kg/d and 29.5 vs. 34.6 kg for ADG and BW change, respectively). Total DMI was similar among treatments when reported as kg/d (6.70 vs. 6.75 kg) or % of BW (2.48 vs. 2.48%), whereas FE was dramatically improved in BAS-administered animals (146 vs. 172 g/kg for CON and BAS, respectively). In summary, BAS administration improved performance of crossbred beef animals for 30 days post-castration.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Toshio Tsuji ◽  
Fumiya Arikuni ◽  
Takafumi Sasaoka ◽  
Shin Suyama ◽  
Takashi Akiyoshi ◽  
...  

AbstractBrain activity associated with pain perception has been revealed by numerous PET and fMRI studies over the past few decades. These findings helped to establish the concept of the pain matrix, which is the distributed brain networks that demonstrate pain-specific cortical activities. We previously found that peripheral arterial stiffness $${\beta }_{\text{art}}$$ β art responds to pain intensity, which is estimated from electrocardiography, continuous sphygmomanometer, and photo-plethysmography. However, it remains unclear whether and to what extent $${\beta }_{\text{art}}$$ β art aligns with pain matrix brain activity. In this fMRI study, 22 participants received different intensities of pain stimuli. We identified brain regions in which the blood oxygen level-dependent signal covaried with $${\beta }_{\text{art}}$$ β art using parametric modulation analysis. Among the identified brain regions, the lateral and medial prefrontal cortex and ventral and dorsal anterior cingulate cortex were consistent with the pain matrix. We found moderate correlations between the average activities in these regions and $${\beta }_{\text{art}}$$ β art (r = 0.47, p < 0.001). $${\beta }_{\text{art}}$$ β art was also significantly correlated with self-reported pain intensity (r = 0.44, p < 0.001) and applied pain intensity (r = 0.43, p < 0.001). Our results indicate that $${\beta }_{\text{art}}$$ β art is positively correlated with pain-related brain activity and subjective pain intensity. This study may thus represent a basis for adopting peripheral arterial stiffness as an objective pain evaluation metric.


2000 ◽  
Vol 41 (1) ◽  
pp. 12
Author(s):  
M.L. Phillips ◽  
L. Williams ◽  
C. Senior ◽  
E.T. Bullmore ◽  
M.J. Brammer ◽  
...  

Author(s):  
Allassane F Ouattara ◽  
Catherine M Bjerum ◽  
Méité Aboulaye ◽  
Olivier Kouadio ◽  
Vanga K Marius ◽  
...  

Abstract Background Ivermectin (IVM) plus albendazole (ALB), or IA, is widely used in mass drug administration (MDA) programs that aim to eliminate lymphatic filariasis (LF) in Africa. However, IVM can cause severe adverse events in persons with heavy Loa loa infections that are common in Central Africa. ALB is safe in loiasis, but more information is needed on its efficacy for LF. This study compared the efficacy and safety of three years of semiannual treatment with ALB to annual IA in persons with bancroftian filariasis. Methods Adults with Wuchereria bancrofti microfilaremia (Mf) were randomized to receive either three annual doses of IA (N=52), six semiannual doses of ALB 400mg (N=45), or six semiannual doses of ALB 800mg (N=47). The primary outcome amicrofilaremia at 36 months. Findings IA was more effective for completely clearing Mf than ALB 400mg or ALB 800mg (79%, CI 67-91; vs. 48%, CI 32-66 and 57%, CI 41-73, respectively). Mean % reductions in Mf counts at 36 months relative to baseline tended to be greater after IA (98%, CI 88-100) than after ALB 400mg (88%, CI 78-98) and ALB 800mg (89%, CI 79-99) (P=0.07 and P=0.06, respectively). Adult worm nest numbers (assessed by ultrasound) were reduced in all treatment groups. Treatments were well tolerated. Interpretation Repeated semiannual treatment with ALB is macrofilaricidal for W. bancrofti and leads to sustained reductions in Mf counts. This is a safe and effective regimen that could be used as MDA to eliminate LF in areas ivermectin cannot be used.


2021 ◽  
Author(s):  
Mohammad Mahdi Eskandary ◽  
Mehdi Hossein Yazdi ◽  
Ehsan Mahjoubi ◽  
Mehdi Kazemi-Bonchenari

Abstract This study aimed to determine the optimal feeding time of microencapsulated sodium butyrate (SB) in whole milk (WM) and starter feed on growth performance and health in dairy calves. Forty-eight Holstein calves (age = 4 d; body weight [BW] = 39.45 ± 2.48 kg) were randomly allocated to 1 of 4 treatment groups (12 calves per treatment) in a completely randomized block design and fed (1) WM without microencapsulated SB (SB0) supplementation; (2) 4 g/d SB added to WM since d 4 to 32 (SB4); (3) 4 g/d SB added to WM since d 61 to 74 and equal amount was added to starter since d 75 to 88 (SB60); and (4) 4 g/d SB added to WM (since d 4 to 74) and the starter (since d 74 to 88) throughout the experiment (SBT). Calves fed SB4 and SBT had lower fecal score during pre-weaning, transition period, and overall period (P = 0.043, P = 0.05, and P = 0.015; respectively). In addition, calves in SB4 and SBT groups decreased the number of days with scours during pre-weaning period, and throughout study (P = 0.035 and P = 0.025; respectively). SB60 calves had greater serum total protein (P < 0.001) during post-weaning period. Post-weaning and overall albumin concentrations were greater in SB4 and SBT calves (P = 0.011), and tended to increase in pre-weaning period compared to control calves (P = 0.06). Based on these results, addition of SB in WM is recommendable for the first month of milk-fed calves life.


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