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1.
Artif Life ; 26(2): 274-306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271631

RESUMO

Evolution provides a creative fount of complex and subtle adaptations that often surprise the scientists who discover them. However, the creativity of evolution is not limited to the natural world: Artificial organisms evolving in computational environments have also elicited surprise and wonder from the researchers studying them. The process of evolution is an algorithmic process that transcends the substrate in which it occurs. Indeed, many researchers in the field of digital evolution can provide examples of how their evolving algorithms and organisms have creatively subverted their expectations or intentions, exposed unrecognized bugs in their code, produced unexpectedly adaptations, or engaged in behaviors and outcomes, uncannily convergent with ones found in nature. Such stories routinely reveal surprise and creativity by evolution in these digital worlds, but they rarely fit into the standard scientific narrative. Instead they are often treated as mere obstacles to be overcome, rather than results that warrant study in their own right. Bugs are fixed, experiments are refocused, and one-off surprises are collapsed into a single data point. The stories themselves are traded among researchers through oral tradition, but that mode of information transmission is inefficient and prone to error and outright loss. Moreover, the fact that these stories tend to be shared only among practitioners means that many natural scientists do not realize how interesting and lifelike digital organisms are and how natural their evolution can be. To our knowledge, no collection of such anecdotes has been published before. This article is the crowd-sourced product of researchers in the fields of artificial life and evolutionary computation who have provided first-hand accounts of such cases. It thus serves as a written, fact-checked collection of scientifically important and even entertaining stories. In doing so we also present here substantial evidence that the existence and importance of evolutionary surprises extends beyond the natural world, and may indeed be a universal property of all complex evolving systems.


Assuntos
Algoritmos , Biologia Computacional , Criatividade , Vida , Evolução Biológica
2.
Med Hypotheses ; 87: 48-60, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26826641

RESUMO

The drug MDMA, commonly known as ecstasy, produces a specific and distinct open hearted mental state, which led to the creation of a new pharmacological class, "entactogens". Extensive literature on its mechanisms of action has come to characterize MDMA as a "messy" drug with multiple mechanisms, but the consensus is that the distinctive entactogenic effects arise from the release of neurotransmitters, primarily serotonin. I propose an alternative hypothesis: The entactogenic mental state is due to the simultaneous direct activation of imidazoline-1 (I1) and serotonin-2 (5-HT2) receptors by MDMA. This hypothesis emerges from "mental organ" theory, which embodies many hypotheses, the most relevant of which are: "Mental organs" are populations of neurons that all express their defining metabotropic receptor, and each mental organ plays a distinct role in the mind, a role shaped by evolution as mental organs evolve by duplication and divergence. Mental organs are the mechanism by which evolution sculpts the mind. Mental organs can be in or out of consciousness. In order for a mental organ to enter consciousness, three things must happen: The mental organ must be activated directly at its defining receptor. 5-HT2 must be simultaneously activated. One of the functions of activated 5-HT2 is to load other simultaneously activated mental organs fully into consciousness. In some cases THC must be introduced to remove long-term blocks mediated by the cannabinoid system. I propose the "primer/probe" method to test these hypotheses. A "primer" is a drug that selectively activates 5-HT2 (e.g. DOB or MEM) or serotonin-1 (5-HT1) and 5-HT2 (e.g. DOET or 2C-B-fly). A "probe" is a drug that activates a receptor whose corresponding mental organ we wish to load into consciousness in order to understand its role in the mind. The mental organ is loaded into consciousness when the primer and probe are taken together, but not when taken separately. For example, the blood pressure medications rilmenidine and moxonidine are selective for imidazoline-1 and can be used to test the hypothesis that the entactogenic mental effects of MDMA are due to loading the imidazoline-1 mental organ into consciousness. The primer/probe method is not limited to testing the specific hypothesis about MDMA and imidazoline, but is a general method for studying the role of mental organs in the mind. For example, the role of dopamine mental organs can be studied by using Parkinson's drugs such as ropinirole or pramipexole as probes.


Assuntos
Alucinógenos/farmacologia , Modelos Neurológicos , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Estado de Consciência/efeitos dos fármacos , Estado de Consciência/fisiologia , Humanos , Receptores de Imidazolinas/efeitos dos fármacos , Receptores de Imidazolinas/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Receptores de Glutamato Metabotrópico/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/fisiologia , Receptores de Neurotransmissores/efeitos dos fármacos , Receptores de Neurotransmissores/fisiologia , Receptores 5-HT2 de Serotonina/efeitos dos fármacos , Receptores 5-HT2 de Serotonina/fisiologia
3.
PLoS One ; 5(2): e9019, 2010 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-20126400

RESUMO

We currently understand the mental effects of psychedelics to be caused by agonism or partial agonism of 5-HT(2A) (and possibly 5-HT(2C)) receptors, and we understand that psychedelic drugs, especially phenylalkylamines, are fairly selective for these two receptors. This manuscript is a reference work on the receptor affinity pharmacology of psychedelic drugs. New data is presented on the affinity of twenty-five psychedelic drugs at fifty-one receptors, transporters, and ion channels, assayed by the National Institute of Mental Health-Psychoactive Drug Screening Program (NIMH-PDSP). In addition, comparable data gathered from the literature on ten additional drugs is also presented (mostly assayed by the NIMH-PDSP). A new method is introduced for normalizing affinity (K(i)) data that factors out potency so that the multi-receptor affinity profiles of different drugs can be directly compared and contrasted. The method is then used to compare the thirty-five drugs in graphical and tabular form. It is shown that psychedelic drugs, especially phenylalkylamines, are not as selective as generally believed, interacting with forty-two of forty-nine broadly assayed sites. The thirty-five drugs of the study have very diverse patterns of interaction with different classes of receptors, emphasizing eighteen different receptors. This diversity of receptor interaction may underlie the qualitative diversity of these drugs. It should be possible to use this diverse set of drugs as probes into the roles played by the various receptor systems in the human mind.


Assuntos
Psicotrópicos/metabolismo , Receptor 5-HT2A de Serotonina/metabolismo , Receptor 5-HT2C de Serotonina/metabolismo , Agonistas do Receptor de Serotonina/metabolismo , Algoritmos , Ligação Competitiva , Alucinógenos/química , Alucinógenos/metabolismo , Alucinógenos/farmacologia , Humanos , Estrutura Molecular , Fenetilaminas/química , Fenetilaminas/metabolismo , Fenetilaminas/farmacologia , Proteoma/agonistas , Proteoma/metabolismo , Psicotrópicos/química , Psicotrópicos/farmacologia , Ensaio Radioligante , Agonistas do Receptor 5-HT2 de Serotonina , Agonistas do Receptor de Serotonina/química , Agonistas do Receptor de Serotonina/farmacologia
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