Habituating drugs

Habituating drugs 76 Halate anions 45 Halide anions 45 Halogen anions 231, 232 Halogen acids 189... 

During the LSD era, those scientists who worried about permanent consequences of habitual drug use were branded as alarmists. But we now see that even purportedly innocent drugs, whose clinical use is widely sanctioned, affect molecular-level events and influence the genes to increase or decrease their products for very long time spans. We need to know much more about the biochemistry of these cascades that turn milliseconds into hours, hours into days, and days into years. 

Shipman s claims that those patients who were found with opiates in their dead body tissues were habitual drug abusers still needed to be quashed. The prosecution brought in an expert forensic hair analyst. As hair grows at a rate of 1 cm per month, the expert could identify evidence of opioid use by quantifying levels in strands of hair. Using mass spectrometry, he discovered that the amount present in the victims hair was consistent with opioid use on only... 

Many job applicants are required to provide blood or urine samples as part of an interview. If a habitual drug user refrains from using drugs in the week before the test, s/he will avoid detection because the drug has long passed through their bodies. 

We have already noted evidence for genetic factors that underlie the preference for and response to caffeine. These factors create a biologically based set of individual difference dimensions that may be modified by experience with the drug. In addition, there is evidence for a number of broader individual difference dimensions that appear to be relevant. These bipolar continua differentiate between subjects who are habitually high in arousal or arousability and those who are habitually low. The factors in question are personality dimensions that theoretically reflect underlying biological continua of arousal or arousability.238 Included among these dimensions are extraversion,58 impulsivity,239240 and sensation-seek-ing.94-241-242 We will take up the first two of these. 

As we noted earlier, caffeine affects not only arousal, but also other behavioral influences such as attentional focus. However, it now appears that these other effects may be secondary to the impact of the drug on arousal and that a multi-factorial model incorporating the inverted-U function may best describe that relationship. Most results in the literature to date are supportive of the biobehavioral model proposed here. However, research on the psychological effects of acute and habitual caffeine... 

The involvement of the cerebellum in the psychoactive effects of marijuana and in changes in rCMR is consistent with the view that THC interacts with the high concentration of CB1 receptors in this brain area. Decreases in the cerebellar rCMR in habitual marijuana users may reflect the effects of chronic exposure to the drug. Functions known to be associated with the cerebellum, such as motor coordination, proprioception, and learning, are adversely affected both during acute marijuana intoxication and in habitual users. 

Addiction may result from inappropriate neuronal plasticity. As discussed in earlier sections of this chapter, drugs of abuse activate the same neuronal pathways as natural reinforcers. However, they do so in a strong and unregulated manner that is hypothesized to lead to abnormal engagement of learning and memory mechanisms, ultimately producing abnormal plasticity in neuronal circuits involved in motivation and decision-making. As a result, the addict becomes narrowly focused on compulsive, habitual behaviors associated with the addictive... 

Whether subthreshold doses in animals can produce any animal neurobehavioral component of the loosening of inhibition and inner-directed attention sought for by some clinicians in using less potent drugs for a kind of psychosynthesis is uncertain. Sensitization and habituation studies implicate raphe function but not in any simple way (32), and pavlovian studies show very low dose effects on sensory processing (39,43). 

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