scholarly journals Modeling the schizophrenias: subunit-specific NMDAR antagonism dissociates frontal δ and hippocampal θ modulation of ~140 Hz oscillations

2017 ◽  
Author(s):  
Benjamin Pittman-Polletta ◽  
Kun Hu ◽  
Bernat Kocsis
Keyword(s):  
Negative Symptoms ◽  
Paradoxical Sleep ◽  
Positive Symptom ◽  
Saline Control ◽  
Cortical Function ◽  
Specific Effects ◽  
High Frequency Oscillations ◽  
Dopaminergic Tone ◽  
Phase Amplitude ◽  
The Impact

ABSTRACTNMDAR antagonism alters mesolimbic, hippocampal, and cortical function, acutely reproducing the positive, cognitive, and negative symptoms of schizophrenia. These physiological and behavioral effects may depend differentially on NMDAR subtype-and region-specific effects. The dramatic electrophysiological signatures of NMDAR blockade in rodents include potentiated high frequency oscillations (HFOs, ~140 Hz), likely generated in mesolimbic structures, and increased HFO phase-amplitude coupling (PAC), a phenomenon related to goal-directed behavior and dopaminergic tone. This study examined the impact of subtype-specific NMDAR antagonism on HFOs and PAC. We found that positive-symptom-associated NR2A-preferring antagonism (NVP-AAM077), but not NR2B-specific antagonism (Ro25-6985) or saline control, replicated increases in HFO power seen with nonspecific antagonism (MK-801). However, PAC following NR2A-preferring antagonism was distinct from all other conditions. While θ-HFO PAC was prominent or potentiated in other conditions, NVP-AAM077 increased δ-HFO PAC and decreased θ-HFO PAC. Furthermore, active wake epochs exhibiting narrowband frontal δ oscillations, and not broadband sleep-associated δ, selectively exhibited δ-HFO coupling, while paradoxical sleep epochs having a high CA1 θ to frontal δ ratio selectively exhibited θ-HFO coupling. Our results suggest: (1) NR2A-preferring antagonism induces oscillopathies reflecting frontal hyperfunction and hippocampal hypofunction; and (2) HFO PAC indexes cortical vs. hippocampal control of mesolimbic circuits.

scholarly journals Childhood adversity and psychosis: generalised or specific effects?

2015 ◽  
Vol 25 (4) ◽  
pp. 349-359 ◽  
Author(s):  
E. Longden ◽  
M. Sampson ◽  
J. Read
Keyword(s):  
Sexual Abuse ◽  
Physical Abuse ◽  
Negative Symptoms ◽  
Childhood Adversity ◽  
Clinical Intervention ◽  
Current Data ◽  
Psychotic Symptoms ◽  
Multiple Exposures ◽  
Specific Effects ◽  
The Impact

Background.This study examines relationships between childhood adversity and the presence of characteristic symptoms of schizophrenia. It was hypothesised that total adversity exposures would be significantly higher in individuals exhibiting these symptoms relative to patients without. Recent proposals that differential associations exist between specific psychotic symptoms and specific adversities was also tested, namely: sexual abuse and hallucinations, physical abuse and delusions, and fostering/adoption and delusions.Method.Data were collected through auditing 251 randomly selected medical records, drawn from adult patients in New Zealand community mental health centres. Information was extracted on presence and subtype of psychotic symptoms and exposure to ten types of childhood adversity, including five types of abuse and neglect.Results.Adversity exposure was significantly higher in patients experiencing hallucinations in general, voice hearing, command hallucinations, visions, delusions in general, paranoid delusions and negative symptoms than in patients without these symptoms. There was no difference in adversity exposure in patients with and without tactile/olfactory hallucinations, grandiose delusions or thought disorder. Indication of a dose–response relationship was detected, in that total number of adversities significantly predicted total number of psychotic symptoms. Although fostering/adoption was associated with paranoid delusions, the hypothesised specificity between sexual abuse and hallucinations, and physical abuse and delusions, was not found. The two adversities showing the largest number of associations with psychotic symptoms were poverty and being fostered/adopted.Conclusions.The current data are consistent with a model of global and cumulative adversity, in which multiple exposures may intensify psychosis risk beyond the impact of single events. Implications for clinical intervention are discussed.

The Impact of Visual Stereotypes on Judgments about Rape

2016 ◽  
Vol 75 (3) ◽  
pp. 133-140
Author(s):  
Robert Busching ◽  
Johannes Lutz
Keyword(s):  
Mental Representations ◽  
Irrelevant Information ◽  
Clear Distinction ◽  
Rape Myth ◽  
Facial Features ◽  
Reverse Correlation ◽  
Correlation Technique ◽  
Specific Effects ◽  
Legal Judgments ◽  
The Impact

Abstract. Legally irrelevant information like facial features is used to form judgments about rape cases. Using a reverse-correlation technique, it is possible to visualize criminal stereotypes and test whether these representations influence judgments. In the first step, images of the stereotypical faces of a rapist, a thief, and a lifesaver were generated. These images showed a clear distinction between the lifesaver and the two criminal representations, but the criminal representations were rather similar. In the next step, the images were presented together with rape scenarios, and participants (N = 153) indicated the defendant’s level of liability. Participants with high rape myth acceptance scores attributed a lower level of liability to a defendant who resembled a stereotypical lifesaver. However, no specific effects of the image of the stereotypical rapist compared to the stereotypical thief were found. We discuss the findings with respect to the influence of visual stereotypes on legal judgments and the nature of these mental representations.

The impact of maternal protein restriction during perinatal life on the response to a septic insult in adult rats

2020 ◽  
pp. 1-8
Author(s):  
Reza Khazaee ◽  
Anastasiya Vinokurtseva ◽  
Lynda A. McCaig ◽  
Cory Yamashita ◽  
Daniel B. Hardy ◽  
...  
Keyword(s):  
Control Diet ◽  
Protein Restriction ◽  
Saline Control ◽  
Female Adult ◽  
Adult Rats ◽  
Male And Female ◽  
Maternal Protein Restriction ◽  
And Control ◽  
The Impact ◽  
Septic Insult

Abstract Although abundant evidence exists that adverse events during pregnancy lead to chronic conditions, there is limited information on the impact of acute insults such as sepsis. This study tested the hypothesis that impaired fetal development leads to altered organ responses to a septic insult in both male and female adult offspring. Fetal growth restricted (FGR) rats were generated using a maternal protein-restricted diet. Male and female FGR and control diet rats were housed until 150–160 d of age when they were exposed either a saline (control) or a fecal slurry intraperitoneal (Sepsis) injection. After 6 h, livers and lungs were analyzed for inflammation and, additionally, the amounts and function of pulmonary surfactant were measured. The results showed increases in the steady-state mRNA levels of inflammatory cytokines in the liver in response to the septic insult in both males and females; these responses were not different between FGR and control diet groups. In the lungs, cytokines were not detectable in any of the experimental groups. A significant decrease in the relative amount of surfactant was observed in male FGR offspring, but this was not observed in control males or in female animals. Overall, it is concluded that FGR induced by maternal protein restriction does not impact liver and lung inflammatory response to sepsis in either male or female adult rats. An altered septic response in male FGR offspring with respect to surfactant may imply a contribution to lung dysfunction.

scholarly journals COMT-by-Sex Interaction Effect on Psychosis Proneness

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Marta de Castro-Catala ◽  
Neus Barrantes-Vidal ◽  
Tamara Sheinbaum ◽  
Artal Moreno-Fortuny ◽  
Thomas R. Kwapil ◽  
...  
Keyword(s):  
Personality Traits ◽  
Susceptibility Gene ◽  
Psychotic Experiences ◽  
Comt Genotype ◽  
Comt Val158met ◽  
Negative Dimension ◽  
Psychosis Proneness ◽  
Specific Effects ◽  
The Impact ◽  
Male Subjects

Schizotypy phenotypes in the general population share etiopathogenic mechanisms and risk factors with schizophrenia, supporting the notion of psychosis as a continuum ranging from nonclinical to clinical deviance. Catechol-O-methyltransferase (COMT) is a candidate susceptibility gene for schizophrenia that is involved in the regulation of dopamine in the prefrontal cortex. Several recent studies have reported a sex difference in the impact of COMT genotype on psychiatric and cognitive phenotypes and personality traits. The present study investigated the association of COMT Val158Met (rs4680) with psychometric positive and negative schizotypy and psychotic experiences in a sample of 808 nonclinical young adults. The main finding was that sex moderates the association of COMT genotype with the negative dimension of both schizotypy and psychotic experiences. Male subjects carrying the Val allele tended to score higher on the negative dimension of both trait and symptom-like measures. The results from the present study are consistent with recent work suggesting an association between negative schizotypy and diminished prefrontal dopamine availability. They support the idea that a biological differentiation underlies the positive and negative schizotypy dimensions. Additionally, these findings contribute to the growing literature on sex-specific effects of COMT on the predisposition to psychiatric disorders and personality traits.

A Group Intervention for Motivational Deficits: Preliminary Investigation of a Blended Care Approach Using Ambulatory Assessment

2021 ◽  
pp. 014544552110476
Author(s):  
Bénédicte Thonon ◽  
Marie-Noëlle Levaux ◽  
Evelyne van Aubel ◽  
Frank Larøi
Keyword(s):  
Group Intervention ◽  
Functional Outcomes ◽  
Negative Symptoms ◽  
Preliminary Investigation ◽  
Activity Level ◽  
Ambulatory Assessment ◽  
Specific Effects ◽  
Daily Step Count ◽  
Care Approach ◽  
Blended Care

Motivational deficits are an important predictor of functional outcomes in individuals with a serious mental illness such as schizophrenia and mood spectrum disorders. The aim of the present study was to explore the feasibility, acceptability, and preliminary efficacy of a group version of “Switch,” an intervention that targets motivational deficits, enriched with an ecological momentary intervention (EMI) approach (i.e., prompts on the participants’ smartphone to encourage the use of trained strategies in their daily life). Eight participants with schizophrenia, schizoaffective, or major depressive disorder entered the study. The intervention took place twice a week for 2 months. Assessment measures included traditional evaluations of motivational negative symptoms, apathy, quality of life and daily functioning, in addition to ambulatory assessment methods strategies, including the experience sampling method (ESM) to assess motivation and related processes, and actigraphy (daily step-count) to assess participants’ activity level. Four participants were considered as non-completers (followed less than 2/3 of the program) and four were considered as completers. Only completers presented a decrease in amotivation/apathy and an improvement in functional outcomes after the intervention and at follow-up. Furthermore, mixed-effects ESM models showed significant interaction effects on multiple processes related to motivation, indicating improvements only in completers: heightened motivation, increased engagement in meaningful and effortful activities, better mood, higher levels of confidence, increased frequency of projection into the future (pleasure anticipation), and of positive reminiscence. This preliminary investigation provides evidence that Switch may be an effective intervention, with specific effects on motivation and associated processes.

Footwear and Elevated Heel Influence On Barbell Back Squat: a Review

2021 ◽  
Author(s):  
Aaron Michael Pangan ◽  
Matthew J Leineweber
Keyword(s):  
Ground Reaction Forces ◽  
Specific Effects ◽  
Back Squat ◽  
Running Shoes ◽  
Different Types ◽  
Reaction Forces ◽  
Joint Loads ◽  
The Impact ◽  
Kinematics And Kinetics ◽  
Full Body

Abstract The back squat is one of the most effective exercises in strengthening the muscles of the lower extremity. Understanding the impact of footwear has on the biomechanics is imperative for maximizing the exercise training potential, preventing injury, and rehabilitating from injury. This review focuses on how different types of footwear affect the full-body kinematics, joint loads, muscle activity, and ground reaction forces in athletes of varying experience performing the weighted back squat. The literature search was conducted using three databases, and fourteen full-text articles were ultimately included in the review. The majority of these studies demonstrated that the choice of footwear directly impacts kinematics and kinetics. Weightlifting shoes were shown to decrease trunk lean and generate more plantarflexion relative to running shoes and barefoot lifting. Elevating the heel through the use of external squat wedges is popular clinical exercise during rehabilitation and was shown to provide similar effects to WLS. Additional research with a broader array of populations, particularly novice and female weightlifters, should be conducted to generalize the research results to non-athlete populations. Further work is also needed to characterize the specific effects of sole stiffness and heel elevation height on squatting mechanics.

Effects of deep brain stimulation on sleep-wake disturbances in patients with Parkinson's disease: A narrative review

2021 ◽  
Vol 19 ◽  
Author(s):  
Yu Jin Jung ◽  
Han-Joon Kim ◽  
Sun Ha Paek ◽  
Beomseok Jeon
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Deep Brain Stimulation ◽  
Brain Stimulation ◽  
Early Stage ◽  
Motor Symptoms ◽  
Specific Effects ◽  
The Impact ◽  
Non Motor Symptoms ◽  
Deep Brain

: Sleep-wake disturbances (SWD) are one of the most common non-motor symptoms in Parkinson's disease (PD) and can appear in the early stage even before the onset of motor symptoms. Deep brain stimulation (DBS) is an established treatment for the motor symptoms in patients with advanced PD. However, the effect of DBS on SWD and its specific mechanisms are not widely understood and remain controversial. In addition to the circuit-mediated direct effect, DBS may improve SWD by an indirect effect such as the resolution of nocturnal motor complications and a reduction of dopaminergic medication. Here, the authors review the recent literatures regarding the impact of DBS on SWD in patients with PD. Furthermore, the selection of the DBS targets and the specific effects of applying DBS to each target on SWD in PD are also discussed.

scholarly journals Patient-specific optimization of automated detection improves seizure onset zone localization based on high frequency oscillations

2020 ◽  
Author(s):  
Casey L. Trevino ◽  
Jack J. Lin ◽  
Indranil Sen-Gupta ◽  
Beth A. Lopour
Keyword(s):  
High Frequency ◽  
Classification Accuracy ◽  
Patient Specific ◽  
Seizure Onset ◽  
Data Set ◽  
Localization Accuracy ◽  
High Frequency Oscillations ◽  
Seizure Onset Zone ◽  
Wide Range ◽  
The Impact

AbstractHigh frequency oscillations (HFOs) are a promising biomarker of epileptogenicity, and automated algorithms are critical tools for their detection. However, previously validated algorithms often exhibit decreased HFO detection accuracy when applied to a new data set, if the parameters are not optimized. This likely contributes to decreased seizure localization accuracy, but this has never been tested. Therefore, we evaluated the impact of parameter selection on seizure onset zone (SOZ) localization using automatically detected HFOs. We detected HFOs in intracranial EEG from twenty medically refractory epilepsy patients with seizure free surgical outcomes using an automated algorithm. For each patient, we assessed classification accuracy of channels inside/outside the SOZ using a wide range of detection parameters and identified the parameters associated with maximum classification accuracy. We found that only three out of twenty patients achieved maximal localization accuracy using conventional HFO detection parameters, and optimal parameter ranges varied significantly across patients. The parameters for amplitude threshold and root-mean-square window had the greatest impact on SOZ localization accuracy; minimum event duration and rejection of false positive events did not significantly affect the results. Using individualized optimal parameters led to substantial improvements in localization accuracy, particularly in reducing false positives from non-SOZ channels. We conclude that optimal HFO detection parameters are patient-specific, often differ from conventional parameters, and have a significant impact on SOZ localization. This suggests that individual variability should be considered when implementing automatic HFO detection as a tool for surgical planning.

scholarly journals A Randomized Clinical Trial of Oxytocin or Galantamine in Schizophrenia: Assessing the Impact on Behavioral, Lexical, and Self-Report Indicators of Social Affiliation

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Kristen R Dwyer ◽  
Alexandra M Andrea ◽  
Christina L G Savage ◽  
Ryan D Orth ◽  
LeeAnn Shan ◽  
...  
Keyword(s):  
Negative Symptoms ◽  
Controlled Trial ◽  
Self Report ◽  
Schizophrenia Spectrum Disorders ◽  
Social Affiliation ◽  
Subjective Responses ◽  
Randomized Controlled ◽  
Schizophrenia Spectrum ◽  
Spectrum Disorders ◽  
The Impact

Abstract Prior studies examining the impact of oxytocin on negative symptoms in schizophrenia have yielded mixed results. The current study explored whether oxytocin can improve more proximal indicators of social affiliation as indicated by changes in behavior, language and subjective indices of social affiliation among individuals with schizophrenia spectrum disorders during a role-play designed to elicit affiliative responses. We tested the hypothesis that daily intranasal oxytocin administered for 6 weeks would improve social affiliation as manifested by increased social skill ratings, use of positive, affiliative, and social words, and subjective responses from a previously published randomized controlled trial. Forty outpatients with schizophrenia or schizoaffective disorder were randomized to the oxytocin, galantamine, or placebo group and completed affiliative role-plays and self-report questionnaires of affect, reactions to the affiliative confederate, and willingness to interact at baseline and post-treatment. Results demonstrated that oxytocin was not effective at improving behavioral or subjective indicators of social affiliation. This study adds to a growing literature that the prosocial effects of oxytocin in schizophrenia are limited or null.

Sign in / Sign up

Export Citation Format

Share Document