Guillaume Fond - Academia.edu (original) (raw)
Papers by Guillaume Fond
The processes underlying the ability tomake decisions about recommended treatments remain poorly ... more The processes underlying the ability tomake decisions about recommended treatments remain poorly understood
in schizophrenia. The aim of this study was to explore the relationships between capacity to consent tomedication
and cognitive biases in 60 schizophrenia patients. Main measures included theMacArthur Competence Assessment
tool for Treatment (MacCAT-T) and the Beck Cognitive Insight Scale (BCIS). After Bonferroni's correction formultiple
correlations, the Self-Reflectiveness dimension of the BCISwas significantly associated with the dimension “Reasoning”
of the MacCAT-T. Cognitive therapy, by enhancing patients' Self-Reflectiveness and considering alternative
explanations, could lead to better capacity to consent to treatment in schizophrenia.
Abnormal decision-making has been described as a key-concept to understand some behavioral distur... more Abnormal decision-making has been described as a key-concept to understand some behavioral disturbances in schizophrenia.
Objectives: to (i) assess performance on decision-making paradigms under ambiguity and risk conditions in patients with schizophrenia compared to healthy controls, and (ii) to study the impact of clinical variables and the executive functioning on decision-making performance.
Methods: Sixty-three stabilized schizophrenia patients and 67 controls were recruited. The Iowa Gambling Task (IGT) and the Game of Dice Task (GDT) were administered to assess respectively decision-making under ambiguity and under risk. These tasks were coupled with executive functions tasks. Schizophrenic symptoms self-reported depression and impulsivity) were evaluated using appropriate questionnaires the same day (PANSS, BDI-II and UPPS). Pharmacological treatments, demographic and clinical variables were reported.
Results: Patients with schizophrenia had impaired performances on both IGT and GDT tasks. We did not find any relationship between the decision-making task performance and clinical variables. Lower gains on the GDT were correlated with executive functioning in schizophrenia.
Conclusion: Decision-making under ambiguity and under risk are both impaired in patients with schizophrenia. Performances on risky conditions were associated with executive functions in schizophrenia. Further studies are needed to explore the association between IGT and GDT performances and decision-making in daily life in schizophrenia. From a clinical perspective, decrease risky and disadvantageous behavior in daily life via the cognitive remediation of executive functioning (and particularly cognitive flexibility and inhibition control) could be an important focus of rehabilitation interventions in schizophrenia.
Clinicians have found that fasting was frequently accompanied by an increased level of vigilance ... more Clinicians have found that fasting was frequently accompanied by an increased level of vigilance and a mood improvement, a subjective feeling of wellbeing, and sometimes of euphoria.
Objective : (i) to provide a systematic review on the impact of therapeutic fasting on mood (ii) to explore the biological mechanisms activated during fasting that could have an effect on brain function with particular focus on mood (we do not discuss here the mechanisms regulating eating behavior). (iii) to recall the principles of safe medical fasting, it’s indications and contraindications.
Method: We explored Medline (1966-present) and Web of Science (1975-present) according to the PRISMA criteria (Preferred Reporting Items for Systematic reviews and Meta-Analysis). The research paradigm was: [fasting AND (mental health OR depressive disorders OR mood OR schizophrenia OR psychosis OR anxiety)].
Results. (i) Many clinical observations relate an early (between day 2 and day 7) effect of fasting on depressive symptoms with an increase in mood, alertness and a sense of tranquility reported by patients. (ii) Many neurobiological mechanisms have been proposed to explain this efficiency such as changes in neurotransmitters, quality of sleep, synthesis of neurotrophic factors. (iii) Therapeutic fasting, following an established protocol, is safe and well tolerated.
Conclusion. Fasting therapy could be particularly interesting in depression, resistant or not, in patients with a 25-40 body mass index, or requiring a rapid response to treatment (suicidal crisis, melancholia). Exploratory studies are needed in anxiety disorders, bipolar disorders and psychotic disorders.
Nanomedicine is defined as the area using nanotechnology's concepts for the benefit of human bein... more Nanomedicine is defined as the area using nanotechnology's concepts for the benefit of human beings’ health and well being.
In this article, we aimed to provide an overview of areas where nanotechnology is applied and how they could be extended to care for psychiatric illnesses.
The main applications of nanotechnology in psychiatry are (i) pharmacology. There are two main difficulties in neuropharmacology: drugs have to pass the blood brain barrier and then to be internalized by targeted cells. Nanoparticles could increase drugs bioavailability and pharmacokinetics, especially improving safety and efficacy of psychotropic drugs. Liposomes, nanosomes, nanoparticle polymers, nanobubbles are some examples of this targeted drug delivery. Nanotechnologies could also add new pharmacological properties, like nanohells and dendrimers (ii) living analysis. Nanotechnology provides technical assistance to in vivo imaging or metabolome analysis (iii) central nervous system modeling. Research teams have succeded to modelize inorganic synapses and mimick synaptic behavior, a step essential for further creation of artificial neural systems. Some nanoparticle assemblies present the same small worlds and free-scale networks architecture as cortical neural networks. Nanotechnologies and quantum physics could be used to create models of artificial intelligence and mental illnesses.
We are not about to see a concrete application of nanomedicine in daily psychiatric practice. Even if nanotechnologies are promising, their safety is still inconsistent and this must be kept in mind. However, it seems essential that psychiatrists do not forsake this area of research the perspectives of which could be decisive in the field of mental illness.
Toxoplasma gondii is the most common protozoan parasite in developed nations. Up to 43% of the Fr... more Toxoplasma gondii is the most common protozoan parasite in developed nations. Up to 43% of the French population may be infected, depending on eating habits and exposure to cats, and almost one third of the world human’s population may be infected. Two types of infection have been described: a congenital form and an acquired form. Although the medical profession treats these latent cases as asymptomatic and clinically unimportant, results of animal studies and recent studies of personality profiles, behavior, and psychomotor performance have led to reconsider this assumption.
Among rats : Parasite cysts are more abundant in amygdalar structures than those found in other regions of the brain. Infection does not influence locomotion, anxiety, hippocampal-dependent learning, fear conditioning (or its extinction) and neophobia in rats. Rats' natural predator is the cat, which is also T. gondii's reservoir. Naturally, rats have an aversion to cat urine, but the parasite suppresses this aversion in rats, thus influencing the infection cycle. Tachyzoites may invade different types of nervous cells, such as neurons, astrocytes and microglial cells in the brain, and Purkinje cells in cerebellum. Intracellular tachyzoïtes manipulate several signs for transduction mechanisms involved in apoptosis, antimicrobial effectors functions, and immune cell maturation. Dopamine levels were 14% higher in mice with chronic infections. These neurochemical changes may be factors contributing to mental and motor abnormalities that accompany or follow toxoplasmosis in rodents and possibly in humans. Moreover, the antipsychotic haloperidol and the mood stabilizer valproic acid most effectively inhibit Toxoplasma growth in vitro with synergistic activity.
Among humans : The effects of the parasite are not due to the manipulation in an evolutionary sense but merely due to neuropathological or neuroimmunological effects of the parasite’s presence. Toxoplasmosis and schizophrenia : epidemiological studies point a role for toxoplasmosis in schizophrenia's etiology, probably during pregnancy and early life, this association being congruent with studies in animal models indicating that animal exposures of the developing brain to infectious agents or immune modulating agents can be associated with behavioral changes that do not appear until the animal reaches full maturity. Psychiatric patients have increased rates of toxoplasmic antibodies, the differences between cases and controls being greatest in individuals who were assayed near the time of the onset of their symptoms. The increase of dopamine in brain of infected subjects can represent the missing link between toxoplasmosis and schizophrenia. Toxoplasmosis and Obsessive Compulsive Disorder (OCD): the seropositivity rate for anti-T.gondii IgG antibodies among OCD patients was found to be significantly higher that the rate in healthy volunteers. Infection of basal ganglia may be implicated in pathogenesis of OCD among Toxoplasma seropositive subjects. Toxoplasmosis and personality: infected men appear to be more dogmatic, less confident, more jealous, more cautious, less impulsive more orderly than others. Conversely, infected women seem warmest, more conscientious, more insecure, more sanctimonious and more persistent than others. It is possible that differences in the level of testosterone may be responsible for the observed behavioral differences between Toxoplasma-infected and Toxoplasma-free subjects.
In the future two major avenues for research seem essential. On one hand, prospective studies and research efforts must still be carried out to understand the mechanisms by which the parasite induces these psychiatric disorders. On the other hand, it has not been demonstrated yet that patients with positive toxoplasmic serology may better respond to haloperidol's or valproic acid's anti-parasitic activity. These results may appear as a major issue in the drug’s prescribing choices and explain variability in response to the treatment of patients with schizophrenia that is not explained by the genetic polymorphism.
We report the case of a 69 year-old female patient who was hospitalized for Diogenes syndrome, de... more We report the case of a 69 year-old female patient who was hospitalized for Diogenes syndrome, defined
by marked self-neglect, social withdrawal and excessive hoarding, leading to squalor. Somatic causes were
eliminated. Her personal history showed an eight-year depressive episode followed by a 20-year hypomanic
episode without remission, followed by a persistent manic episode associated with Diogenes syndrome for four
years. The Diogenes syndrome was successfully treated with mood stabilizers. Mood disorders – in particular
chronic mania (i.e. a manic episode lasting more than two years) – should be considered in cases of Diogenes
syndrome and in current classifications.
Introduction. -The aim of this article is to provide an overview of existing studies on gay and l... more Introduction. -The aim of this article is to provide an overview of existing studies on gay and lesbian parenthood and child development. Although 200,000 to 300,000 children could be concerned in 2010 in France, there is a lack of research on this issue in our country. Background. -Research among children raised by homosexual parents involves methodological issues, such as defining homosexual families, sampling cases and controls, and choosing structured or semi-structured evaluations. The fact that homosexual marriage, adoption and insemination are not presently legal in France could explain that only one study has been conducted in France in 2000 among 58 children raided by homosexual parents. This study concluded that these children did not show an increased rate of behavior or anxiety disorders. Literature findings. -Concerns about lesbian parenting have focused on the absence of a father, the homosexual orientation of the mother, and their negative consequences on the development of the children. Research on parenting and child rearing has repeatedly compared lesbian and heterosexual families, and in the last 30 years a growing body of studies on lesbian parents and the development of their children has been published. Studies about child development, sexual orientation, gender identity, gender role behavior, emotional/behavioral development, social relationships and cognitive functioning showed no difference between children of lesbian mothers and those of heterosexual parents. Likewise, parental functioning, the mothers' psychological health and maternal skills were not significantly different among lesbian mothers than among heterosexual mothers. In studies concerning gay fathers, findings generally indicate no differences in sexual orientation, socialization, or psychological outcomes in children of gay fathers compared to children of heterosexual fathers. However, the first study on the adult attachment style dimensions of adult women who had gay or bisexual fathers suggested that they were significantly less comfortable with closeness and intimacy, less able to trust and depend on others, and experienced more anxiety in relationships than women with heterosexual fathers. This survey has not been argued among lesbian families or coparentality. Discussion. -Variables related to family processes, such as relationship quality, are currently considered more important predictors of children's adjustment in homosexual families than sexual orientation. The major part of the literature focused on children aged four to 16 and the small sample size (often less than 30 children) limit the validity of these data. However, very little is known about psychological characteristics or well-being of adult children of lesbian and gay parents, and research should be pursued in the future. Social relationships of children raised by homosexual families, their experience of difference, and the discrimination are also likely to vary with the culture of each country and was not evaluated to our knowledge to date in cross-cultural studies using standardized questionnaires. Conclusion. -Our practice must find new reference marks to understand the stakes and the difficulties of these configurations for a better empathy with the child and his/her family.
The processes underlying the ability tomake decisions about recommended treatments remain poorly ... more The processes underlying the ability tomake decisions about recommended treatments remain poorly understood
in schizophrenia. The aim of this study was to explore the relationships between capacity to consent tomedication
and cognitive biases in 60 schizophrenia patients. Main measures included theMacArthur Competence Assessment
tool for Treatment (MacCAT-T) and the Beck Cognitive Insight Scale (BCIS). After Bonferroni's correction formultiple
correlations, the Self-Reflectiveness dimension of the BCISwas significantly associated with the dimension “Reasoning”
of the MacCAT-T. Cognitive therapy, by enhancing patients' Self-Reflectiveness and considering alternative
explanations, could lead to better capacity to consent to treatment in schizophrenia.
Abnormal decision-making has been described as a key-concept to understand some behavioral distur... more Abnormal decision-making has been described as a key-concept to understand some behavioral disturbances in schizophrenia.
Objectives: to (i) assess performance on decision-making paradigms under ambiguity and risk conditions in patients with schizophrenia compared to healthy controls, and (ii) to study the impact of clinical variables and the executive functioning on decision-making performance.
Methods: Sixty-three stabilized schizophrenia patients and 67 controls were recruited. The Iowa Gambling Task (IGT) and the Game of Dice Task (GDT) were administered to assess respectively decision-making under ambiguity and under risk. These tasks were coupled with executive functions tasks. Schizophrenic symptoms self-reported depression and impulsivity) were evaluated using appropriate questionnaires the same day (PANSS, BDI-II and UPPS). Pharmacological treatments, demographic and clinical variables were reported.
Results: Patients with schizophrenia had impaired performances on both IGT and GDT tasks. We did not find any relationship between the decision-making task performance and clinical variables. Lower gains on the GDT were correlated with executive functioning in schizophrenia.
Conclusion: Decision-making under ambiguity and under risk are both impaired in patients with schizophrenia. Performances on risky conditions were associated with executive functions in schizophrenia. Further studies are needed to explore the association between IGT and GDT performances and decision-making in daily life in schizophrenia. From a clinical perspective, decrease risky and disadvantageous behavior in daily life via the cognitive remediation of executive functioning (and particularly cognitive flexibility and inhibition control) could be an important focus of rehabilitation interventions in schizophrenia.
Clinicians have found that fasting was frequently accompanied by an increased level of vigilance ... more Clinicians have found that fasting was frequently accompanied by an increased level of vigilance and a mood improvement, a subjective feeling of wellbeing, and sometimes of euphoria.
Objective : (i) to provide a systematic review on the impact of therapeutic fasting on mood (ii) to explore the biological mechanisms activated during fasting that could have an effect on brain function with particular focus on mood (we do not discuss here the mechanisms regulating eating behavior). (iii) to recall the principles of safe medical fasting, it’s indications and contraindications.
Method: We explored Medline (1966-present) and Web of Science (1975-present) according to the PRISMA criteria (Preferred Reporting Items for Systematic reviews and Meta-Analysis). The research paradigm was: [fasting AND (mental health OR depressive disorders OR mood OR schizophrenia OR psychosis OR anxiety)].
Results. (i) Many clinical observations relate an early (between day 2 and day 7) effect of fasting on depressive symptoms with an increase in mood, alertness and a sense of tranquility reported by patients. (ii) Many neurobiological mechanisms have been proposed to explain this efficiency such as changes in neurotransmitters, quality of sleep, synthesis of neurotrophic factors. (iii) Therapeutic fasting, following an established protocol, is safe and well tolerated.
Conclusion. Fasting therapy could be particularly interesting in depression, resistant or not, in patients with a 25-40 body mass index, or requiring a rapid response to treatment (suicidal crisis, melancholia). Exploratory studies are needed in anxiety disorders, bipolar disorders and psychotic disorders.
Nanomedicine is defined as the area using nanotechnology's concepts for the benefit of human bein... more Nanomedicine is defined as the area using nanotechnology's concepts for the benefit of human beings’ health and well being.
In this article, we aimed to provide an overview of areas where nanotechnology is applied and how they could be extended to care for psychiatric illnesses.
The main applications of nanotechnology in psychiatry are (i) pharmacology. There are two main difficulties in neuropharmacology: drugs have to pass the blood brain barrier and then to be internalized by targeted cells. Nanoparticles could increase drugs bioavailability and pharmacokinetics, especially improving safety and efficacy of psychotropic drugs. Liposomes, nanosomes, nanoparticle polymers, nanobubbles are some examples of this targeted drug delivery. Nanotechnologies could also add new pharmacological properties, like nanohells and dendrimers (ii) living analysis. Nanotechnology provides technical assistance to in vivo imaging or metabolome analysis (iii) central nervous system modeling. Research teams have succeded to modelize inorganic synapses and mimick synaptic behavior, a step essential for further creation of artificial neural systems. Some nanoparticle assemblies present the same small worlds and free-scale networks architecture as cortical neural networks. Nanotechnologies and quantum physics could be used to create models of artificial intelligence and mental illnesses.
We are not about to see a concrete application of nanomedicine in daily psychiatric practice. Even if nanotechnologies are promising, their safety is still inconsistent and this must be kept in mind. However, it seems essential that psychiatrists do not forsake this area of research the perspectives of which could be decisive in the field of mental illness.
Toxoplasma gondii is the most common protozoan parasite in developed nations. Up to 43% of the Fr... more Toxoplasma gondii is the most common protozoan parasite in developed nations. Up to 43% of the French population may be infected, depending on eating habits and exposure to cats, and almost one third of the world human’s population may be infected. Two types of infection have been described: a congenital form and an acquired form. Although the medical profession treats these latent cases as asymptomatic and clinically unimportant, results of animal studies and recent studies of personality profiles, behavior, and psychomotor performance have led to reconsider this assumption.
Among rats : Parasite cysts are more abundant in amygdalar structures than those found in other regions of the brain. Infection does not influence locomotion, anxiety, hippocampal-dependent learning, fear conditioning (or its extinction) and neophobia in rats. Rats' natural predator is the cat, which is also T. gondii's reservoir. Naturally, rats have an aversion to cat urine, but the parasite suppresses this aversion in rats, thus influencing the infection cycle. Tachyzoites may invade different types of nervous cells, such as neurons, astrocytes and microglial cells in the brain, and Purkinje cells in cerebellum. Intracellular tachyzoïtes manipulate several signs for transduction mechanisms involved in apoptosis, antimicrobial effectors functions, and immune cell maturation. Dopamine levels were 14% higher in mice with chronic infections. These neurochemical changes may be factors contributing to mental and motor abnormalities that accompany or follow toxoplasmosis in rodents and possibly in humans. Moreover, the antipsychotic haloperidol and the mood stabilizer valproic acid most effectively inhibit Toxoplasma growth in vitro with synergistic activity.
Among humans : The effects of the parasite are not due to the manipulation in an evolutionary sense but merely due to neuropathological or neuroimmunological effects of the parasite’s presence. Toxoplasmosis and schizophrenia : epidemiological studies point a role for toxoplasmosis in schizophrenia's etiology, probably during pregnancy and early life, this association being congruent with studies in animal models indicating that animal exposures of the developing brain to infectious agents or immune modulating agents can be associated with behavioral changes that do not appear until the animal reaches full maturity. Psychiatric patients have increased rates of toxoplasmic antibodies, the differences between cases and controls being greatest in individuals who were assayed near the time of the onset of their symptoms. The increase of dopamine in brain of infected subjects can represent the missing link between toxoplasmosis and schizophrenia. Toxoplasmosis and Obsessive Compulsive Disorder (OCD): the seropositivity rate for anti-T.gondii IgG antibodies among OCD patients was found to be significantly higher that the rate in healthy volunteers. Infection of basal ganglia may be implicated in pathogenesis of OCD among Toxoplasma seropositive subjects. Toxoplasmosis and personality: infected men appear to be more dogmatic, less confident, more jealous, more cautious, less impulsive more orderly than others. Conversely, infected women seem warmest, more conscientious, more insecure, more sanctimonious and more persistent than others. It is possible that differences in the level of testosterone may be responsible for the observed behavioral differences between Toxoplasma-infected and Toxoplasma-free subjects.
In the future two major avenues for research seem essential. On one hand, prospective studies and research efforts must still be carried out to understand the mechanisms by which the parasite induces these psychiatric disorders. On the other hand, it has not been demonstrated yet that patients with positive toxoplasmic serology may better respond to haloperidol's or valproic acid's anti-parasitic activity. These results may appear as a major issue in the drug’s prescribing choices and explain variability in response to the treatment of patients with schizophrenia that is not explained by the genetic polymorphism.
We report the case of a 69 year-old female patient who was hospitalized for Diogenes syndrome, de... more We report the case of a 69 year-old female patient who was hospitalized for Diogenes syndrome, defined
by marked self-neglect, social withdrawal and excessive hoarding, leading to squalor. Somatic causes were
eliminated. Her personal history showed an eight-year depressive episode followed by a 20-year hypomanic
episode without remission, followed by a persistent manic episode associated with Diogenes syndrome for four
years. The Diogenes syndrome was successfully treated with mood stabilizers. Mood disorders – in particular
chronic mania (i.e. a manic episode lasting more than two years) – should be considered in cases of Diogenes
syndrome and in current classifications.
Introduction. -The aim of this article is to provide an overview of existing studies on gay and l... more Introduction. -The aim of this article is to provide an overview of existing studies on gay and lesbian parenthood and child development. Although 200,000 to 300,000 children could be concerned in 2010 in France, there is a lack of research on this issue in our country. Background. -Research among children raised by homosexual parents involves methodological issues, such as defining homosexual families, sampling cases and controls, and choosing structured or semi-structured evaluations. The fact that homosexual marriage, adoption and insemination are not presently legal in France could explain that only one study has been conducted in France in 2000 among 58 children raided by homosexual parents. This study concluded that these children did not show an increased rate of behavior or anxiety disorders. Literature findings. -Concerns about lesbian parenting have focused on the absence of a father, the homosexual orientation of the mother, and their negative consequences on the development of the children. Research on parenting and child rearing has repeatedly compared lesbian and heterosexual families, and in the last 30 years a growing body of studies on lesbian parents and the development of their children has been published. Studies about child development, sexual orientation, gender identity, gender role behavior, emotional/behavioral development, social relationships and cognitive functioning showed no difference between children of lesbian mothers and those of heterosexual parents. Likewise, parental functioning, the mothers' psychological health and maternal skills were not significantly different among lesbian mothers than among heterosexual mothers. In studies concerning gay fathers, findings generally indicate no differences in sexual orientation, socialization, or psychological outcomes in children of gay fathers compared to children of heterosexual fathers. However, the first study on the adult attachment style dimensions of adult women who had gay or bisexual fathers suggested that they were significantly less comfortable with closeness and intimacy, less able to trust and depend on others, and experienced more anxiety in relationships than women with heterosexual fathers. This survey has not been argued among lesbian families or coparentality. Discussion. -Variables related to family processes, such as relationship quality, are currently considered more important predictors of children's adjustment in homosexual families than sexual orientation. The major part of the literature focused on children aged four to 16 and the small sample size (often less than 30 children) limit the validity of these data. However, very little is known about psychological characteristics or well-being of adult children of lesbian and gay parents, and research should be pursued in the future. Social relationships of children raised by homosexual families, their experience of difference, and the discrimination are also likely to vary with the culture of each country and was not evaluated to our knowledge to date in cross-cultural studies using standardized questionnaires. Conclusion. -Our practice must find new reference marks to understand the stakes and the difficulties of these configurations for a better empathy with the child and his/her family.