- Joined
- Mar 19, 2018
- Messages
- 9,358
- Reputation
- 1,568
Nah, schizo can really fuck you up, most schizos end up socially isolate and about half of them attempt suicide.
The dopamine hypothesis of schizophrenia didn't end up panning out so well. Today the NMDAR hypofunction hypothesis has attracted the most interest.
true, but it's not like dopamine doesn't cause a lot of the positive symptoms, it's just that glutamatergic and dopaminergic systems are related, with the glutamatergic/nmda dysfunction being closer to the root of the issue in schizophrenia; dopaminergic stimulants alone can definitely still cause psychosis, so oldmate above is right in essence that too much dopamine will make you batshit crazy ie. a gigachadThe dopamine hypothesis of schizophrenia didn't end up panning out so well. Today the NMDAR hypofunction hypothesis has attracted the most interest.
Beyond the Dopamine Hypothesis to the NMDA Glutamate Receptor Hypofunction Hypothesis of Schizophrenia | CNS Spectrums | Cambridge Core
Beyond the Dopamine Hypothesis to the NMDA Glutamate Receptor Hypofunction Hypothesis of Schizophrenia - Volume 12 Issue 4 - Stephen M. Stahlwww.cambridge.org
I only started studying matters after research had progressed to largely rejecting the dopamine hypothesis and had started focusing on the NMDAR hypofunction hypothesis though, so I am not that familiar with the more classical research.
cabergoline?So how what are legit ways to dopaminemax besides caber
en.wikipedia.org
they still do treat it with inverse serotonin agonists / serotonin antagonists, which would just as much so indicate a potential continued adherence to the serotonergic hypothesis of schizophrenia. The modern treatments -- last I knew -- was going through clinical trials still, and they are NMDAR positive allosteric modulators, which indicates a coming around to the NMDAR hypofunction hypothesis. How discouraging that the history of schizophrenia treatment has been one of consistent hope and disappointment.
Site Ki (nM) Action 5-HT1A 423 Antagonist 5-HT1B 14.9 Antagonist 5-HT1D 84.6 Antagonist 5-HT2A 0.17 Inverse agonist 5-HT2B 61.9 Inverse agonist 5-HT2C 12.0 Inverse agonist 5-HT5A 206 Antagonist 5-HT6 2,060 Antagonist 5-HT7 6.60 Irreversible
antagonist[41]α1A 5.0 Antagonist α1B 9.0 Antagonist α2A 16.5 Antagonist α2B 108 Antagonist α2C 1.30 Antagonist D1 244 Antagonist D2 3.57 Antagonist D2S 4.73 Antagonist D2L 4.16 Antagonist D3 3.6 Inverse agonist D4 4.66 Antagonist D5 290 Antagonist H1 20.1 Inverse agonist H2 120 Inverse agonist mACh >10,000 Negligible
https://www.cell.com/fulltext/S0896-6273(03)00757-8Schizophrenia is a serious psychiatric illness that is responsible for a substantial proportion of mental illness worldwide. Symptoms include hallucination, delusions, thought disorder and negative symptoms, including poverty of thought and emotion, and social withdrawal. Early theories of schizophrenia implicated disturbed serotonin (5-HT) neurotransmission, but these were largely overshadowed by the dopamine theory of schizophrenia, which became established after the introduction of chlorpromazine.
The introduction of several new antipsychotic drugs in the last decade promised to treat schizophrenia more efficaciously than conventional antipsychotics, and without the unwanted side effects. These drugs, which were modeled after clozapine, reduce dopamine receptor function. However, a discouraging outcome of treatment with these drugs is emerging: they do not substantially improve clinical outcome for schizophrenia and, worse, some produce dangerous side effects, such as weight gain, diabetes, and elevations in blood lipids.
The heterogeneity of results isn't that surprising to me. Schizophrenia is thought today to be a set of phenotypes, each of which having an autistic inversion. As a set of distinct phenotypes, it's pretty much tautological that it is a heterogeneous condition.Over the past two decades, accumulating evidence has implicated the role of glutamatergic dysfunction in the pathophysiology of schizophrenia. There has been growing interest in glutamatergic system as a promising target for treatment of schizophrenia spectrum illness and several medications and compounds have been investigated to date. In the present study, we aim to provide a comprehensive review of clinical studies of glutamatergic agents in treatment of schizophrenia. We further discuss the heterogeneity of the results, the overall discouraging outcomes and future directions for investigating glutamatergic medications in schizophrenia.
Liemburg et al40 studied connectivity within the DMN and hypothesized that poor-insight patients (n=19) would show greater connectivity impairment than their good-insight peers (n=25). Insight grouping was assigned on the basis of the PANSS insight item (G12). All subjects underwent resting fMRI. Results showed that “schizophrenia patients with relatively preserved insight showed stronger connectivity than patients with poor insight in the anterior cingulate cortex and precuneus, both key regions in self-reflective processing. These findings tentatively support the hypothesis that poor insight may be related to impaired self-related processing.�? In other words, poor insight was associated with a relative breakdown of DMN connectivity and operations.
Those are both neurological presentations associated with schizophrenia; however, they are not equivalent. The breakdown of the default mode network is associated with clinical insight deficits; the reduced volume of the vlpfc with cognitive insight deficits.Orfei et al30 used the BCIS along with structural and diffusion tensor MRI neuroimaging techniques (latter to inspect white matter architectural organization) to study the neuroanatomy of cognitive insight in schizophrenia, comparing 45 patients with schizophrenia to 45 healthy control subjects. The results showed a correlation between insight as measured by the BCIS self-reflectiveness index and lower gray matter volume in the right ventrolateral prefrontal cortex (VLPFC). The VLPFC is involved in working memory and decision making. The findings suggest that a reduced VLPFC volume corresponds with a diminished capacity to entertain alternative explanations about one’s misperceptions leading to impairment in awareness of illness.
I would only expect the NMDAR PAMs to work in cases with diminished vlPFC volume, for they essentially will serve to strengthen one of the primary functions of the vlPFC -- maintaining activation of the task positive network despite emotional distractions in the environment.There are self-administered, validated tools as well, such as the Beck Cognitive Insight Scale (BCIS),11 which is based on a separation of the concepts of “cognitive insight�? and “clinical insight.�? Clinical insight is described as the awareness of mental illness requiring treatment, while cognitive insight encompasses the patient’s ability to evaluate, reappraise, and modify distorted beliefs or misperceptions. These interpretations are regulated at a “higher level�? of cognition, also called metacognition, allowing clinicians to assess self-regulating and self-monitoring functions of thought processes. The BCIS assesses a patient’s objectivity about delusional thinking, previous errors, reattribution of false explanations, and ability to receive corrective information from others. It includes self-reflectiveness and self-certainty subscales in order to measure willingness and capacity to entertain alternate explanations and over-confidence in validity of beliefs.
In schizophrenia with normal vlPFC volume but lesioning of the default mode network, I wouldn't expect improvement from NMDAR PAMs.The ventrolateral prefrontal cortex (vlPFC) is a subdivision of the prefrontal cortex. Its involvement in modulating existing behavior and emotional output given contextual demands has been studied extensively using cognitive reappraisal studies and emotion-attention tasks. Cognitive reappraisal studies indicate the vlFPC’s role in reinterpreting stimuli, and reducing or augmenting responses. Studies using emotion-attention tasks demonstrate the vlFPC’s function in ignoring emotional distractions while the brain is engaged in performing other tasks.[6]https://en.wikipedia.org/wiki/Inter..._executive_brain_systems#cite_note-mitchell-6
A prominent feature of the human brain’s global architecture is the anticorrelation of default-mode vs. task-positive systems. Here, we show that administration of an NMDA glutamate receptor antagonist, ketamine, disrupted the reciprocal relationship between these systems in terms of task-dependent activation and connectivity during performance of delayed working memory. Furthermore, the degree of this disruption predicted task performance and transiently evoked symptoms characteristic of schizophrenia.
I would expect that group of schizophrenics -- with diminished deactivation of the default mode network during working memory task -- to be the one that benefited from the NMDAR positive allosteric modulators.Whitfield-Gabrieli et al39 studied patients with schizophrenia; young, at-risk, first-degree relatives; and unaffected controls using fMRI during alternating conditions of wakeful rest and a focused working memory task. While the unaffected controls showed predictable deactivation of DMN during active task, the patients and relatives showed diminished deactivation, as well as greater activity in right DLPFC. This finding has essentially been replicated twice by two other research groups.
cabergoline?
what i meant is that i was under the impression that nmdar hypofunction causes the positive symptoms mostly because nmdar regulates dopamine function (hence dopaminergic drugs coming with a risk of psychosis), and that in that sense the two theories are more complimentary than exclusive, and afaik clozapine et al does generally work well for positive symptoms, the reason they aren't great for clinical outcomes is because they make the negative symptoms (ie. laziness, anhedonia, braindeadness) worse, just ask mvp, he's living that reality right nowI suppose they do use dopamine antagonists for treating schizophrenia, so that indicates that the people prescribing such things for schizophrenia still have some degree of belief in the dopamine hypothesis. It could just take decades for the old wisdom to work its way through our society though -- hard to say. There is a lot of old research in support of the dopamine hypothesis, but before that I think it was the serotonin hypothesis. Then again
![]()
Risperidone - Wikipedia
en.wikipedia.org
they still do treat it with inverse serotonin agonists / serotonin antagonists, which would just as much so indicate a potential continued adherence to the serotonergic hypothesis of schizophrenia. The modern treatments -- last I knew -- was going through clinical trials still, and they are NMDAR positive allosteric modulators, which indicates a coming around to the NMDAR hypofunction hypothesis. How discouraging that the history of schizophrenia treatment has been one of consistent hope and disappointment.
![]()
The 5-HT hypothesis of schizophrenia - PubMed
Schizophrenia is a serious psychiatric illness that is responsible for a substantial proportion of mental illness worldwide. Symptoms include hallucination, delusions, thought disorder and negative symptoms, including poverty of thought and emotion, and social withdrawal. Early theories of...www.ncbi.nlm.nih.gov
https://www.cell.com/fulltext/S0896-6273(03)00757-8
Glutamate modulators for treatment of schizophrenia
Over the past two decades, accumulating evidence has implicated the role of glutamatergic dysfunction in the pathophysiology of schizophrenia. There h…www.sciencedirect.com
The heterogeneity of results isn't that surprising to me. Schizophrenia is thought today to be a set of phenotypes, each of which having an autistic inversion. As a set of distinct phenotypes, it's pretty much tautological that it is a heterogeneous condition.
Those are both neurological presentations associated with schizophrenia; however, they are not equivalent. The breakdown of the default mode network is associated with clinical insight deficits; the reduced volume of the vlpfc with cognitive insight deficits.
I would only expect the NMDAR PAMs to work in cases with diminished vlPFC volume, for they essentially will serve to strengthen one of the primary functions of the vlPFC -- maintaining activation of the task positive network despite emotional distractions in the environment.
In schizophrenia with normal vlPFC volume but lesioning of the default mode network, I wouldn't expect improvement from NMDAR PAMs.
I would expect that group of schizophrenics -- with diminished deactivation of the default mode network during working memory task -- to be the one that benefited from the NMDAR positive allosteric modulators.
and it is known that it can cause -- at least acute -- psychosis.Infusions of the dopamine releasing agent amphetamine or the dopamine uptake inhibitor nomifensine resulted in a dose-dependent increase in the overflow of dopamine.
However, amphetamine likely causes deactivation of the default mode network,Amphetamines may induce symptoms of psychosis very similar to those of acute schizophrenia spectrum psychosis. This has been an argument for using amphetamine-induced psychosis as a model for primary psychotic disorders. To distinguish the two types of psychosis on the basis of acute symptoms is difficult. However, acute psychosis induced by amphetamines seems to have a faster recovery and appears to resolve more completely compared to schizophrenic psychosis.
Conclusions/Significance
These findings provide evidence that dopamine transporters modulate neural activity in the DMN and anterior cingulate gyrus during visuospatial attention. Our findings suggest that dopamine modulates attention in part by regulating neuronal activity in posterior parietal cortex including precuneus (region involved in alertness) and cingulate gyrus (region deactivated in proportion to emotional interference). These findings suggest that the beneficial effects of stimulant medications (increase dopamine by blocking DAT) in inattention reflect in part their ability to facilitate the deactivation of the DMN.
Zhou et al.109 found evidence for increased resting state connectivity in the DMN in a schizophrenic group, along with increased anticorrelation between the DMN and another brain network known as the task-positive network (TPN). Such anticorrelations are found in healthy individuals110 and are thought to reflect the ongoing switching of attention between the external and internal words, mediated respectively by the TPN and DMN.
Schizophrenia is waking reality processed through the dreaming brain
It's massively complex and hard to think of though. It's hard to reconcile amphetamine inducing a psychosis similar to schizophrenia's with amphetamine (probably) causing diminished activation of the default mode network. I find that it is really cognitively demanding trying to process all of the pertinent information into a coherent whole. There is just such nuance to neuropsychiatry, and so much inversion that it makes my head spin. It's amazing how essentially inverted conditions can both present as one condition (the extreme ends of the autism-psychosis spectrum being two states of catatonia that have been difficult for the researchers to tease apart).In contrast to the default mode network-like activation patterns of normal REM sleep , brain regions activated during lucid dreaming comprise substantial parts of the frontoparietal control network .
didnt readOne thing to keep in mind is that psychosis is a symptom; conversely, schizophrenia is a condition that presents with psychosis. I'm not very familiar with the dopamine mechanism for psychosis, but amphetamine increase synaptic dopamine (as a dopamine releasing agent, it causes the synaptic vesicle of a dopamine neuron to release its neurotransmitter into the synapse).
![]()
The effect of intrastriatal application of directly and indirectly acting dopamine agonists and antagonists on the in vivo release of acetylcholine measured by brain microdialysis
The effect of intrastriatal application of D-1, D-2 and indirect dopaminergic drugs on the release of striatal acetylcholine as a function of the post-implantation intervals was studied using in vivo microdialysis. The dopamine, D-2 agonists LY 171555 and (−)N0437 inhibited the release of...link.springer.com
and it is known that it can cause -- at least acute -- psychosis.
However, amphetamine likely causes deactivation of the default mode network,
Task-Positive Network - an overview | ScienceDirect Topics
www.sciencedirect.com
Is a sort of artist's conception I've fashioned.
![]()
Neural correlates of insight in dreaming and psychosis
The idea that dreaming can serve as a model for psychosis has a long and honourable tradition, however it is notoriously speculative. Here we demonstr…www.sciencedirect.com
It's massively complex and hard to think of though. It's hard to reconcile amphetamine inducing a psychosis similar to schizophrenia's with amphetamine (probably) causing diminished activation of the default mode network. I find that it is really cognitively demanding trying to process all of the pertinent information into a coherent whole. There is just such nuance to neuropsychiatry, and so much inversion that it makes my head spin. It's amazing how essentially inverted conditions can both present as one condition (the extreme ends of the autism-psychosis spectrum being two states of catatonia that have been difficult for the researchers to tease apart).
indeedOne thing to keep in mind is that psychosis is a symptom; conversely, schizophrenia is a condition that presents with psychosis.
indeedIt's massively complex and hard to think of though.
GeniusOne thing to keep in mind is that psychosis is a symptom; conversely, schizophrenia is a condition that presents with psychosis. I'm not very familiar with the dopamine mechanism for psychosis, but amphetamine increase synaptic dopamine (as a dopamine releasing agent, it causes the synaptic vesicle of a dopamine neuron to release its neurotransmitter into the synapse).
![]()
The effect of intrastriatal application of directly and indirectly acting dopamine agonists and antagonists on the in vivo release of acetylcholine measured by brain microdialysis
The effect of intrastriatal application of D-1, D-2 and indirect dopaminergic drugs on the release of striatal acetylcholine as a function of the post-implantation intervals was studied using in vivo microdialysis. The dopamine, D-2 agonists LY 171555 and (−)N0437 inhibited the release of...link.springer.com
and it is known that it can cause -- at least acute -- psychosis.
However, amphetamine likely causes deactivation of the default mode network,
Task-Positive Network - an overview | ScienceDirect Topics
www.sciencedirect.com
Is a sort of artist's conception I've fashioned.
![]()
Neural correlates of insight in dreaming and psychosis
The idea that dreaming can serve as a model for psychosis has a long and honourable tradition, however it is notoriously speculative. Here we demonstr…www.sciencedirect.com
It's massively complex and hard to think of though. It's hard to reconcile amphetamine inducing a psychosis similar to schizophrenia's with amphetamine (probably) causing diminished activation of the default mode network. I find that it is really cognitively demanding trying to process all of the pertinent information into a coherent whole. There is just such nuance to neuropsychiatry, and so much inversion that it makes my head spin. It's amazing how essentially inverted conditions can both present as one condition (the extreme ends of the autism-psychosis spectrum being two states of catatonia that have been difficult for the researchers to tease apart).
Another twat who thinks hes smarter than he is blaming others for his downfalls. Delusional confirmed.Your dopamine system isn't black and white like that. I have an IQ of 132, because of the way my dopamine system worked throughout my youth.
Some kids push themselves to the limit in social interactions, sports etc. I did the same, but at school when I was making calculations, giving presentations, etc. Always trying to be the best, pushing myself to the limit, going beyond the assignment. This is what got me the high IQ in the first place.
And that's exactly what got me fucked up, since kids hate smart kids. And being smart doesn't make you attractive, therefore getting you a negative halo and fucking up your social status.