Drugs conditions

For patients, this was especially true if they were in the real drug condition 89 per cent of patients given the real antidepressants correctly figured out that they were in the drug group. In contrast, only 59 per cent of patients in the placebo group guessed correctly.9... 

Le Foil B., Diaz J., Sokoloff P. A single cocaine exposure increases BDNF and D3 receptor expression implications for drug-conditioning. Neuroreport. 16 175, 2005. 

Fig. 3 Activation difference between the rapid visual information processing (RVIP) and control tasks in smokers after administration of placebo and nicotine patches. The graphs show the percent change in activation (from baseline) during performance of each task in smokers in the two drug conditions. After receiving nicotine, smokers demonstrated better task performance and more task-related activity in the parietal (A and B) and occipital (C and D) cortices compared to the parallel measures after they received placebo (Kumari et al. 2003)...

Kumari et al, (2003) 12 2 mg nicotine, subcutaneously N-Back Nicotine improved accuracy in all N-back conditions and reduced response times during the more demanding conditions of the task. Irrespective of drug condition, frontal and parietal regions were activated with increasing memory load. Nicotine, however, increased brain activation in the anterior cingulate (0-back, 1-back, 2-back), superior frontal (1-back, 2-back), and left superior parietal cortex (1-back, 2-back, 3-back), in the 3-back condition, nicotine reduced activation in the right superior parietal cortex. 

Hypersensitivity to the drug conditions that might predispose patients to priapism (eg, sickle cell anemia or trait, multiple myeloma, leukemia) patients with anatomical deformation of the penis patients with penile implants (intracavernosal) use in women, children, or newborns use in men for whom sexual activity is inadvisable or contraindicated for sexual intercourse with a pregnant woman unless the couple uses a condom barrier. 

Figure 7.2 After high doses of the experimental drugs, changes (from baseline) in initial (p re stimulus) pupil diameter, constriction velocity, and constriction amplitude varied as a function of the drug condition and time.

The constriction amplitude of the light reflex differed significantly among the treatment conditions (Figure 7.2). A two-way ANOVA indicated significant differences among drug conditions... 

Acquas E, Di Chiara G (1994) Dl receptor blockade stere-ospecifically impairs the acquisition of drug-conditioned place preference and place aversion. Behav Pharmacol 5 555-560... 

Acquas E, Carboni E, Garau L, Di Chiara G (1990) Blockade of acquisition of drug-conditioned place aversion by 5-HT3antagonists. Psychopharmacology 100 459 163 Amalric M, Cline EJ, Martinez JL Jr, Bloom FE, Koob GF (1987) Rewarding properties of P-endorphin as measured by conditioned place preference. Psychopharmacology 91 14-19... 

Excitotoxic NAc core lesions slow down the acquisition of first order schedules of heroin self-administration but do not affect already established responding (Alderson et al., 2001 Hutcheson et al., 2001). An impairment of instrumental learning by these lesions has been excluded on the basis of the observation that responding was still sensitive to changes in the outcome value. On the basis of the above studies, Cardinal et al. (2002) maintain that the NAc core is not critical for instrumental learning and interpret the effects of NAc core lesions in acquisition as the result of an impairment of the motivational arousal elicited by drug-conditioned stimuli. Consistent with this explanation is the observation that NAc core lesions prevent acquisition of second-order schedules... 

Recently, we have completed a series of studies comparing the effect of Pavlovian stimuli conditioned to morphine and food on DA relase in the NAc shell, NAc core and PFCX (Bassareo et al., in preparation). A more detailed account of these studies will be given in the Section Drug-induced stimulation of DA transmission and abnormal Pavlovian incentive learning. Here it will suffice to say that while drug-conditioned stimuli elicit a sustained release of DA in the NAc shell but not in the NAc core, food-conditioned stimuli release DA in the NAc core but not in the shell (Figs. 6-8). 

Moreover, while in the incentive learning hypothesis abnormal motivation is the result of the abnormal properties of the stimulation of DA transmission by the drug, in the incentive sensitization theory abnormal motivation is the result of the excessive activation of DA transmission by stimuli conditioned to the drug. An excessive activation of DA transmission by drug-conditioned stimuli is also predicted by the incentive learning hypothesis but as secondary to the excessive impact acquired by drug-conditioned stimuli as a result of abnormal incentive learning. 

These observations are consistent with the prediction that sensitization induced by repeated drug exposure increases the basic responsiveness of DA neurons to stimuli (Robinson and Berridge, 1993). However, this conclusion, while consistent with the prediction of the theory, turns out to be deleterious for its validity as a model of human addiction. In fact, since sensitization increases the incentive properties of any appetitive stimulus, not only of drug-related ones, it can hardly account for a cardinal feature of drug addiction, namely that the excessive impact over behavior exerted by drug-conditioned stimuli is reciprocated by a reduced impact by stimuli conditioned to nondrug rewards. 

These observations demonstrate the striking differences existing between drug-conditioned and food-conditioned stimuli in their differential ability to affect DA transmission in the NAc shell and core and the different adaptive consequences exerted by these conditioned stimuli on the ability of drug and food reward to stimulate DA transmission in the NAc shell. 

Acquas E, Carboni E, Leone P, Di Chiara G (1989) SCH 23390 blocks drug-conditioned place preference and place-aversion anhedonia (lack of reward) or apathy (lack of motivation) after dopamine-receptor blockade. 

Joseph Jacobs, Some Drug Conditions During the War Between the States, 1861-1865, SHSP 33 (Richmond, VA The Society, 1905), pp. 161-187. Originally read before the American Pharmaceutical Association at its Baltimore meeting in 1898 and published in the Proc. APhA 46 (1898) 192-213. 

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