In recent years, a debate has emerged on whether bodily sensations are typically accompanied by a sense of body ownership, namely a distinctive experience of one's body or body part as one's own. Realists about the sense of body ownership heavily rely on evidence from experimentally-induced bodily illusions (e.g., the rubber hand illusion) and pathological disownership syndromes (e.g. somatoparaphrenia). In this chapter, I will introduce novel evidence regarding body disownership syndromes induced by psychoactive drugs rather than pathological conditions, (...) and discuss its relevance to the debate on the sense of body ownership. (shrink)

Philosophical and empirical research on bodily awareness has mostly focused so far on bodily disorders – such as anorexia nervosa, somatoparaphrenia, or xenomelia (body integrity dysphoria) – and bodily illusions induced in an experimental setting – such as the rubber hand illusion, or the thermal grid illusion. Studying these conditions can be illuminating to investigate a broad range of issues about the nature, function, and etiology of bodily experience. However, a number of psychoactive compounds can also induce a remarkably (...) wide variety of bodily effects that have received little attention despite their relevance to these issues. Some of these effects are similar to those associated with bodily disorders or experimental bodily illusions, while others appear to be unique. The purpose of this chapter is to provide an overview of these lesser known bodily effects of psychoactive compounds, and outline some ways in which they can bear on recent debates regarding bodily awareness and bodily ownership. (shrink)

Two meta-analyses of pharmacological research are presented, demonstrating that psychoactive drugs have consistent effects on EEG and sleep outside of their effects on REM sleep, and demonstrating that drugs other than those affecting sleep neurotransmitter systems and REM sleep can also alter reported nightmare occurrence. These data suggest that the neurobiology data terrain outside activation-synthesis may include sleep and dream electrophysiology, cognitive reports of dreaming, effects of alterations in consciousness on dreaming, immunology and host defense, and clinical therapies for sleep (...) disorders. (shrink)

Studies have shown that both serotonin and glutamate receptor systems play a crucial role in the mechanisms underlying drug-induced synesthesia. The specific nature of these mechanisms, however, continues to remain elusive. Here we propose two distinct hypotheses for how synesthesia triggered by hallucinogens in the serotonin-agonist family may occur. One hypothesis is that the drug-induced destabilization of thalamic projections via GABAergic neuronal circuits from sensory areas leads to a disruption of low-level, spontaneous integration of multisensory stimuli. (...) This sort of integration regularly occurs when spatial and temporal attributes match. Destabilization of feedback loops, however, can result in incongruent experiences or binding of random thalamus activation with sensory input in a particular sensory modality. The second hypothesis builds on embodied cognition, cases in which visual images of external stimuli activate task-related neural regions. On this proposal, binding processes that do not normally generate awareness become accessible to consciousness as a result of decreased attentional discrimination among incoming stimuli. (shrink)

There is growing evidence that dopamine replacement therapy (DRT) used to treat Parkinson’s Disease can cause compulsive behaviours and impulse control disorders (ICDs), such as pathological gambling, compulsive buying and hypersexuality. Like more familiar drug-based forms of addiction, these iatrogenic disorders can cause significant harm and distress for sufferers and their families. In some cases, people treated with DRT have lost their homes and businesses, or have been prosecuted for criminal sexual behaviours. In this article we first examine the (...) evidence that these disorders are caused by DRT. If it is accepted that DRT cause compulsive or addictive behaviours in a significant minority of individuals, then the following ethical and clinical questions arise: Under what circumstances is it ethical to prescribe a medication that may induce harmful compulsive behaviours? Are individuals treated with DRT morally responsible and hence culpable for harmful or criminal behaviour related to their medication? We conclude with some observations of the relevance of DRT-induced ICDs for our understanding of addiction and identify some promising directions for future research and ethical analysis. (shrink)

Despite some principal similarities, there is no systematic comparison between the different types of synesthesia . This comprehensive review compares the three principal types of synesthesia and focuses on their phenomenological features and their relation to different etiological models. Implications of this comparison for the validity of the different etiological models are discussed.Comparison of the three forms of synesthesia show many more differences than similarities. This is in contrast to their representation in the literature, where they are discussed in many (...) respects as being virtually similar. Noteworthy is the much broader spectrum and intensity with the typical drug-induced synesthesias compared to genuine and acquired synesthesias. A major implication of the phenomenological comparison in regard to the etiological models is that genuine and acquired synesthesias point to morphological substrates, while drug-induced synesthesia appears to be based on functional changes of brain activity. (shrink)

There is converging evidence that high doses of hallucinogenic drugs can produce significant alterations of self-experience, described as the dissolution of the sense of self and the loss of boundaries between self and world. This article discusses the relevance of this phenomenon, known as “drug-induced ego dissolution (DIED)”, for cognitive neuroscience, psychology and philosophy of mind. Data from self-report questionnaires suggest that three neuropharmacological classes of drugs can induce ego dissolution: classical psychedelics, dissociative anesthetics and agonists of the (...) kappa opioid receptor (KOR). While these substances act on different neurotransmitter receptors, they all produce strong subjective effects that can be compared to the symptoms of acute psychosis, including ego dissolution. It has been suggested that neuroimaging of DIED can indirectly shed light on the neural correlates of the self. While this line of inquiry is promising, its results must be interpreted with caution. First, neural correlates of ego dissolution might reveal the necessary neurophysiological conditions for the maintenance of the sense of self, but it is more doubtful that this method can reveal its minimally sufficient conditions. Second, it is necessary to define the relevant notion of self at play in the phenomenon of DIED. This article suggests that DIED consists in the disruption of subpersonal processes underlying the “minimal” or “embodied” self, i.e., the basic experience of being a self rooted in multimodal integration of self-related stimuli. This hypothesis is consistent with Bayesian models of phenomenal selfhood, according to which the subjective structure of conscious experience ultimately results from the optimization of predictions in perception and action. Finally, it is argued that DIED is also of particular interest for philosophy of mind. On the one hand, it challenges theories according to which consciousness always involves self-awareness. On the other hand, it suggests that ordinary conscious experience might involve a minimal kind of self-awareness rooted in multisensory processing, which is what appears to fade away during DIED. (shrink)

Bayne and Carter argue that the mode of consciousness induced by psychedelic drugs does not fit squarely within the traditional account of modes as levels of consciousness, and favor instead a multi-dimensional account according to which modes of consciousness differ along several dimensions—none of which warrants a linear ordering of modes. We discuss the assumption that psychedelic drugs induce a single or paradigmatic mode of consciousness, as well as conceptual issues related to Bayne and Carter’s main argument against the (...) traditional account. Finally, we raise a set of questions about the individuation of dimensions selected to differentiate modes of consciousness that could be addressed in future discussions of the multi-dimensional account. (shrink)

ObjectiveThis study aims to investigate anxiety and its influencing factors in patients with drug-induced liver injury (DILI).Materials and MethodsNinety-four patients with DILI were enrolled and evaluated with a self-rating anxiety scale (SAS). According to the anxiety score, they were divided into four groups: the non-anxiety, mild anxiety, moderate anxiety, or severe anxiety groups, and the scores were analyzed based on demographic and biochemical indicators.ResultsOf the 94 patients with DILI, 63 did not have anxiety and 31 had anxiety (32.9%), (...) of which 27 had mild, 3 had moderate, and 1 had severe anxiety. There were no statistically significant differences in gender, age, occupation, and level of education between the groups (F= 1.42,H= 2.361,H= 6.751,H= 1.796, andP> 0.05); anxiety score and degree of anxiety between the types of drugs that led to the liver injury (H= 0.812,H= 1.712, andP> 0.05); anxiety score between the different degrees of liver injury (H= 2.836,H= 4.957,P> 0.05); or length of hospital stay or prognosis between the degrees of anxiety (F= 1.487,H= 0.761,P> 0.05). However, there were statistically significant differences in the degree of anxiety between different degree and types of liver injury (H= 7.981,H= 8.208,P< 0.05).ConclusionPatients with DILI may have anxiety, especially mild anxiety. The occurrence of anxiety in patients with DILI is not related to gender, age, occupation, or level of education but may be related to the degree and type of liver injury. Anxiety has no impact on the length of stay in hospital or the prognosis of the DILI. These findings may contribute to the development of management strategies for patients with DILI. (shrink)

Both W9 and OP3‐4 were known to bind the receptor activator of NF‐κB ligand (RANKL), inhibiting osteoclastogenesis. Recently, both peptides were shown to stimulate osteoblast differentiation; however, the mechanism underlying the activity of these peptides remains to be clarified. A primary osteoblast culture showed that rapamycin, an mTORC1 inhibitor, which was recently demonstrated to be an important serine/threonine kinase for bone formation, inhibited the peptide‐induced alkaline phosphatase activity. Furthermore, both peptides promoted the phosphorylation of Akt and S6K1, an upstream (...) molecule of mTORC1 and the effector molecule of mTORC1, respectively. In the in vivo calvarial defect model, W9 and OP3‐4 accelerated BMP‐2‐induced bone formation to a similar extent, which was confirmed by histomorphometric analyses using fluorescence images of undecalcified sections. Our data suggest that these RANKL‐binding peptides could stimulate the mTORC1 activity, which might play a role in the acceleration of BMP‐2‐induced bone regeneration by the RANKL‐binding peptides. (shrink)

Effective therapies are now available that can stop the progression of HIV infection and significantly delay the onset of AIDS. The “highly active antiretroviral therapy” (HAART) is a combination of potent antiretroviral drugs such as viral protease inhibitors or nucleoside-analogue reverse-transcriptase inhibitors, that has a variety of serious side effects, including lipodystrophy, a pathology characterized by accumulation of visceral fat, breast adiposity, cervical fat-pads, hyperlipidemia, insulin resistance as well as fat wasting in face and limbs. There is still an open (...) debate that concerns the precise responsibility of HAART as well as metabolic pathways and mechanisms that are involved in the onset of lipodystrophy. The similarities with multiple symmetric lipomatosis (MSL), in which mitochondria impairment plays a crucial role, lead to the hypothesis that drug-induced damages to mitochondrial DNA are able to alter mitochondria functionality to an extent that is similar to what occurs in MSL. In addition, several evidences indicate that HAART is also linked to a deregulated production of tumour necrosis factor-α, which uses mitochondria as intracellular targets. In this paper, we review data concerning the role of mitochondria in the pathogenesis of lipodystrophy, and advance a unifying hypothesis involving either direct or indirect effects of the drugs employed during HAART. BioEssays 23:1070–1080, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

Despite the recent discovery that thalidomide causes limb defects by targeting highly angiogenic, immature blood vessels, several challenges still remain and new ones have arisen. These include understanding the drug's species specificity, determining molecular target(s) in the endothelial cell, shedding light on the molecular basis of phocomelia and producing a form of the drug that is clinically effective without having side effects. Now that the trigger of thalidomide‐induced teratogenesis has been uncovered, a framework is proposed, incorporating and (...) uniting previous models of thalidomide action, explaining how thalidomide causes not just limb defects, but also all the other defects it induces. (shrink)

Despite the remarkable achievements of novel targeted anti‐cancer drugs, most therapies only produce remission for a limited time, resistance to treatment, and relapse, often being the ultimate outcome. Drug resistance is due to highly efficient adaptive strategies utilized by cancer cells. Exogenous and endogenous stress stimuli are known to induce first‐line responses, capable of re‐establishing cellular homeostasis and determining cell fate decisions. Cancer cells may also mount second‐line adaptive strategies, such as the mutator response. Hypermutable subpopulations of cells may (...) expand under severe selective stress, thereby accelerating the emergence of adapted clones. As with first‐line protective responses, these strategies appear highly conserved, and are found in yeasts and bacteria. We hypothesize that evolutionarily conserved programs rheostatically regulate mutability in fluctuating environments, and contribute to drug resistance in cancer cells. Elucidating the conserved genetic and molecular mechanisms may present novel opportunities to increase the effectiveness of cancer therapies. (shrink)

We propose a discrete time branching process to model the appearance of drug resistance under treatment. Under our assumptions at every discrete time a pathogen may die with probability 1−p or divide in two with probability p. Each newborn pathogen is drug resistant with probability μ. We start with N drug sensitive pathogens and with no drug resistant pathogens. We declare the treatment successful if all pathogens are eradicated before drug resistance appears. The model predicts (...) that success is possible only if p<1/2. Even in this case the probability of success decreases exponentially with the parameter m=μN. In particular, even with a very potent drug (i.e. p very small) drug resistance is likely if m is large. (shrink)

Participant safety and data integrity, critical in trials of new investigational drugs, are achieved through honest participant report and precision in the conduct of procedures. HIV prevention post-trial access studies in middle-income countries potentially offer participants many benefits including access to proven efficacious but unlicensed technologies, ancillary care that often exceeds local standards-of-care, financial reimbursement for participation and possibly unintended benefits if participants choose to share or sell investigational drugs. This case study examines the possibility that this combination of benefits (...) may constitute an undue inducement for some participants in middle-income countries, where economic challenges are prevalent. A case study is presented of a single participant in a cohort of 382 participants who used concealment, fabrication and deception to ensure eligibility for a post-trial access study of an unlicensed HIV prevention technology at potential risk to her health and that of her fetus. A root cause analysis revealed her desire to access HIV prevention during an unplanned pregnancy with a partner whose faithfulness was in question. Researchers should consider implementation of systems to efficiently identify similar cases without inconveniencing the majority of participants Trial registration number NCT01691768. (shrink)

The ability to convert human somatic cells into induced pluripotent stem cells (iPSCs) is allowing the production of custom‐tailored cells for drug discovery and for the study of disease phenotypes at the cellular and molecular level. IPSCs have been derived from patients suffering from a large variety of disorders with different severities. In many cases, disease related phenotypes have been observed in iPSCs or their lineage‐specific progeny. Several proof of concept studies have demonstrated that these phenotypes can be (...) reversed in vitro using approved drugs. However, several challenges must be overcome to take full advantage of this technology. Here, we highlight recent advances in the field and discuss the main challenges associated with this technology as it applies to disease modelling. (shrink)

The demonstration that pluripotent stem cells could be generated by somatic cell reprogramming led to wonder if these so-called induced pluripotent stem (iPS) cells would extend our investigation capabilities in the cancer research field. The first iPS cells derived from cancer cells have now revealed the benefits and potential pitfalls of this new model. iPS cells appear to be an innovative approach to decipher the steps of cell transformation as well as to screen the activity and toxicity of anticancer (...) drugs. A better understanding of the impact of reprogramming on cancer cell-specific features as well as improvements in culture conditions to integrate the role of the microenvironment in their behavior may strengthen the epistemic interest of iPS cells as model systems in oncology. (shrink)

Soman, an anticholinesterasic neurotoxic drug, induces epileptic seizures during severe intoxication. Their trigger conditions still remain unknown and a great variability between animals is observed. The butterfly model in the catastrophe theory has been used to explain these triggering conditions.We have developed a technique allowing, in freely moving rats, the « in vivo » determination of three sets of neurophysiological data, followed before and during a soman intoxication. For the same rat, we associated cortical acetylcholinesterase (AChE) activity by microdialysis (...) with both the assay of extracellular acetylcholine (ACh) concentrations and electroencephalographic (EEG) recording and power spectrum analysis (gamma band). Data have been analysed to define the critical parameters which lead to the epileptic fit. (shrink)

Medical professionals often deny patients who inject opioids a second or third heart valve replacement, even if such a surgery is medically indicated. However, such a position is not well defended. As this paper demonstrates, the ethical literature on the topic too often fails to develop and apply an ethical lens to analyse the issue of multiple valve replacements. This paper addresses this lacuna by analysing the case of Mr Walsh, a composite case which protects the identity of any one (...) patient, through the principlist approach of Beauchamp and Childress. It argues that the hospital should offer Mr Walsh, a second valve replacement because the procedure is: medically indicated, autonomously requested, non-maleficent, beneficent and does not violate a formal account of justice. The paper concludes with clinical ethical guidelines for valve surgery for patients with opioid use disorder. (shrink)

Discovery of a second, inducible prostaglandin synthase provides explanations for many previously puzzling observations, but also raises new questions about prostanoid synthesis. A cis‐acting sequence closely related to the cyclic AMP response element has been shown to play a role in both basal and induced prostaglandin synthase 2 gene expression. Aspirin and other currently available non‐steroidal anti‐inflammatory drugs that inhibit prostaglandin synthase activity do not effectively discriminate between the inducible prostaglandin synthase 2 and constitutive prostaglandin synthase 1 enzymes. Identification (...) of a second prostaglandin synthase, induced by inflammatory stimuli, initiated a search for isoform‐specific inhibitors. Use of prostaglandin synthase 2 specific inhibitors and antisense oligonucleotides has led to the suggestion that specific ligands activate alternative pathways of prostanoid production, using one of the prostaglandin synthase isoforms preferentially. The coupling mechanisms by which these pathways are activated in response to alternative stimuli should provide additional routes of intervention in prostanoid production. (shrink)

Ultraviolet (UV) radiation is a very common carcinogen in our environment, but epidemiological data on the relationship between skin cancers and ambient solar UV radiation are very restricted. In hairless mice the process of UV carcinogenesis can be studied in depth. Experiments with this animal model have yielded quantitative data on how tumor development depends on dose, time and wavelength of the UV radiation. In combination with epidemiological data, these experimental results can be transposed to humans. Comparative studies on molecular, (...) cellular and physiological changes in mouse and man can further our fundamental understanding of UV carcinogenesis in man. This is likely to improve risk assessments such as those related to a stratospheric ozone depletion, and to yield well‐targeted intervention schemes, e.g. prescribing a specific drug or diet, for high‐risk individuals. (shrink)

Introduction: We live in a society that encourages self-medication and one reason is the availability of drugs that do not require a prescription and are easily accessible, the abuse of these have important implications for the health of the general population; being the most commonly used drugs: analgesics, antibiotics, antihistamines and others. Objective: Determine the causes that induce self-medication in freshmen and fifth year of the Faculty of Medicine of the Universidad Mayor, Real y Pontificia de San Francisco Xavier de (...) Chuquisaca - Bolivia, 2012. Methodology: Quantitative and descriptive cross-sectional approach. A sample of 284 students which they apply structural survey was obtained. Results.A high percentage of students who are self-medicating themselves without.medical.supervision. Conclusions: We can say that self-medication on freshmen and fifth year of medical school at the University Of San Francisco Xavier De Chuquisaca is induced by influence of social circle (friends and parents), advertising of certain medications, access to internet and lack of time. (shrink)

Cytochrome P450IIE1 is involved in the metabolic activation of many xenobiotics involved with human toxicity. In particular, cellular concentrations of P450IIE1 are significantly induced by the most widely abused drug in our society today, alcohol. As a result, the synthesis and degradation of this form of P450 has significant health consequences. The regulation of the steady‐state concentration of P450IIE1 is an extremely complex process. The enzyme is regulated by transcriptional activation, mRNA stabilization, increased mRNA translatability and decreased protein (...) degradation. The principal mechanism which controls the induction process depends on the chemical nature of the inducer, the age, and the nutritional and hormonal status of the animal. There also appear to be significant sex differences in the expression of P450IIE1. It is entirely possible that the regulation of the enzyme concentration under any given set of conditions will involve all of the mechanisms to different extents. (shrink)

Prematurely born children who have underdeveloped lungs may suffer a potentially fatal condition called respiratory distress syndrome. A U.S. company developed a drug, called Surfaxin, to treat such poorly functioning lungs. A placebo-controlled study was planned in four Latin American countries. At the time, in 2001, four treatments were already on the market, although not available to the research populations used in the study. This case is usually discussed as part of the standard of care debate or offered as (...) an example of exploitation. However, what concerns us in this case is rather the choice given to the parents of a prematurely born child under these circumstances: “You can give consent for your child's participation in this study. Half of the babies enrolled will receive sham air and are as likely to die as if they had not enrolled. The other half will receive an active treatment and are more likely to survive.” The parents can vastly increase their baby's chances of survival by participating in the study. Can the consent be voluntary? Do the parents have any meaningful choice? (shrink)

Scientific interest in drug-induced mystical experiences reemerged in the 1990s. This warrants reexamining the philosophical issues surrounding such studies: Do psychedelic drugs cause mystical experiences? Are drug-induced experiences the same in nature as other mystical experiences? Does the fact that mystical experiences can be induced by drugs invalidate or validate mystical cognitive claims? Those questions will be examined here. An overview of the scientific examination of drug-induced mystical experiences is included, as is a (...) brief overview of the history of the use of psychedelic drugs in religion. (shrink)

An increasing number of drugs removed from the market because of unacceptable toxicity raises concerns regarding preapproval testing of drug safety. In the present paper it is postulated that the non-inferiority type of trial should be abandoned in favor of the superiority trial with active controls and less stringent (p<0.1, both for efficacy and toxicity) statistics. This approach will increase sensitivity of detection of drug-induced adverse effects at the expense of increasing false positive results regarding the difference (...) in efficacy between the tested and reference drug. Such a move will increase the protection of future patients. In addition, the proposed design is far more acceptable from the clinical (e.g. no need to specify the statistically expected “unimportant” number of deaths) and ethical points of view, as well as being favored by the strong incentive of involved parties. In the second part of this paper arguments are presented in favor of the hypothesis that placebo (still used in some superiority trials) does not induce adverse effects. The assertion that placebo may induce adverse effects is probably biased by the nature of the clinical experiment. Such a conclusion is supported by studies indicating that placebo-induced adverse effects are disease — and treatment — specific. The modification of clinical trials according to the proposed changes may increase the trials’ sensitivity at detecting adverse effects of drugs. (shrink)

Modeling metastasis in animal systems has been an important focus for developing cancer therapeutics. Xenopus laevis is a well‐established model, known for its use in identifying genetic mechanisms underlying diseases and disorders in humans. Prior literature has suggested that the drug, ivermectin, can be used in Xenopus to induce melanocytes to convert into a metastatic melanoma‐like state, and thus could be ideal for testing possible melanoma therapies in vivo. However, there are notable inconsistencies between ivermectin studies in Xenopus and (...) the application of ivermectin in mammalian systems, that are relevant to cancer and melanoma research. In this review, we examine the ivermectin‐induced phenotypes in Xenopus, and we explore the current uses of ivermectin in human research. We conclude that while ivermectin may be a useful drug for many biomedical purposes, it is not ideal to induce a metastatic melanocyte phenotype in Xenopus for testing the effects of potential melanoma therapeutics. (shrink)

The emphasis in human pluripotent stem cell (hPSC) technologies has shifted from cell therapy to in vitro disease modelling and drug screening. This review examines why this shift has occurred, and how current technological limitations might be overcome to fully realise the potential of hPSCs. Details are provided for all disease‐specific human induced pluripotent stem cell lines spanning a dozen dysfunctional organ systems. Phenotype and pharmacology have been examined in only 17 of 63 lines, primarily those that model (...) neurological and cardiac conditions. Drug screening is most advanced in hPSC‐cardiomyocytes. Responses for almost 60 agents include examples of how careful tests in hPSC‐cardiomyocytes have improved on existing in vitro assays, and how these cells have been integrated into high throughput imaging and electrophysiology industrial platforms. Such successes will provide an incentive to overcome bottlenecks in hPSC technology such as improving cell maturity and industrial scalability whilst reducing cost. (shrink)

Caffeine, a known CNS stimulant is given as an adjunct component in most abused drugs which could be fatal with repeated administration in many circumstances. This paper presents a study to investigate the effect of repeated administration of caffeine at high dose on rat liver, and discusses ethical and policy issues of caffeine use. Long Evans rats were treated with pure caffeine solution in distilled water through intragastric route once daily for consecutive 56 days. Three groups of rats recognized as (...) low dose, high dose and control group received 6mg caffeine / kg BW, 12mg caffeine / kg BW and distilled water, respectively. Rat plasma was examined for liver transaminases and alkaline phosphatases concentrations which were significantly increased in plasma as compared to the control. Both rat plasma and liver homogenate were subjected to estimate malondialdehyde, advanced oxidation protein product, nitric oxide, antioxidant enzyme catalase, glutathione and superoxide dismutase activity. MDA, AOPP, NO levels increased and SOD activity decreased significantly in both plasma and liver as compared to those of control where as CAT and GSH activity remain unchanged. Rat liver tissues were studied histochemically with Hematoxylin and Eosin, and Picro Sirius Red staining. Significantly increased infiltration of inflammatory cells and progressive deposition of collagen fibre were visible in liver tissue of caffeine treated both dose groups as compared to the control. Long term administration of caffeine at higher dose, significantly contributes to liver inflammation and consequent fibrogenesis. This raises significant ethical and policy issues. (shrink)

It has been well documented that the auditory system in the superior temporal cortex is responsible for processing basic auditory sound features, such as sound frequency and intensity, while the prefrontal cortex is involved in higher-order auditory functions, such as language processing and auditory episodic memory. The temporal auditory cortex has vast forward anatomical projections to the prefrontal auditory cortex, connecting with the lateral, medial, and orbital parts of the prefrontal cortex. The connections between the auditory cortex and the prefrontal (...) cortex thus help in localizing, recognizing, and comprehending external auditory inputs. In addition, the medial prefrontal cortex (MPFC) is believed to be a core region of episodic memory retrieval and is one of the most important regions in the default mode network (DMN). However, previous neural evidence with regard to the comparison between basic auditory processing and auditory episodic memory retrieval mainly comes from fMRI studies. The specific neural networks and the corresponding critical frequency bands of neuronal oscillations underlying the two auditory functions remain unclear. In the present study, we reported results of direct cortical stimulations during stereo-electro-encephalography (SEEG) recording in a patient with drug-resistant epilepsy. Electrodes covered the superior temporal gyrus, the operculum and the insula cortex of bilateral hemispheres, the prefrontal cortex, the parietal lobe, the anterior and middle cingulate cortex, and the amygdala of the left hemisphere. Two types of auditory hallucinations were evoked with direct cortical stimulations, which were consistent with the habitual seizures. The noise hallucinations, i.e., “I could hear buzzing noises in my head,” were evoked with the stimulation of the superior temporal gyrus. The episodic memory hallucinations “I could hear a young woman who was dressed in a red skirt saying: What is the matter with you?,” were evoked with the stimulation of MPFC. The patient described how she had met this young woman when she was young and that the woman said the same sentence to her. Furthermore, by analyzing the high gamma power (HGP) induced by direct electrical stimulation, two dissociable neural networks underlying the two types of auditory hallucinations were localized. Taken together, the present results confirm the hierarchical processing of auditory information by showing the different involvements of the primary auditory cortex vs. the prefrontal cortex in the two types of auditory hallucinations. (shrink)

Considerable hope surrounds the use of disease‐specific pluripotent stem cells to generate models of human disease allowing exploration of pathological mechanisms and search for new treatments. Disease‐specific human embryonic stem cells were the first to provide a useful source for studying certain disease states. The recent demonstration that human somatic cells, derived from readily accessible tissue such as skin or blood, can be converted to embryonic‐like induced pluripotent stem cells (hiPSCs) has opened new perspectives for modelling and understanding a (...) larger number of human pathologies. In this review, we examine the opportunities and challenges for the use of disease‐specific pluripotent stem cells in disease modelling and drug screening. Progress in these areas will substantially accelerate effective application of disease‐specific human pluripotent stem cells for drug screening. (shrink)