Reinforcers, natural

ANSWER Yes. We think that it is a neat hypothesis. In the absence of natural reinforcement forces, craving for cocaine becomes more intense. I think one of the things that would be important is to figure out some way of testing it. 

Natural reinforcers and drugs of abuse use similar circuits 912 The neuronal circuitry underlying drug craving has been intensely studied to develop strategies for preventing relapse 912... 

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... 

Natural reinforcers. Pleasurable consequences that are the natural result of a behavior. 

Like other natural reinforcers (water, food, sex -somatosensory genital stimulation, and sweet taste), sexual pheromones should stimulate the neural circuits responsible for reward signaling. Current ideas on the neuroanatomy of reward are based... 

Natural reinforcements have been used for a very long time ... 

The renewed interest in natural reinforcements may continue because ... 

Preclinical studies suggest that D3 DR antagonists reduce the influence of environmental stimuli associated with nicotine, but do not reduce response to aversive stimuli or natural reinforcers. For example, smdies have shown that D3 DR antagonists reduced nicotine-conditioned place preference in rats, with no reduction in place preference to food (Le Foil et al. 2005 Pak et al. 2006) They also reduced nicotine-conditioned locomotor activity in rats (Le Loll et al. 2003 Pak et al. 2006). These results may be especially relevant to smoking cessation, because conditioning processes appear to play a large role in smoking behavior. 

Opioid systems contribute to the regulation of naturally reinforced behaviors (i.e., sexual behavior, feeding, drinking, and social behavior) (Rodgers and Cooper, 1988) and to the rewarding effects of artificial reinforcers, such as chemical rewards as cocaine and ethanol (van Ree et ah, 1999). 

Channel charasteristics Natural Reinforced Man-made (ditch)... 

Figure I. Comparison of the properties of different natural reinforcement fibres.

Rodriguez E, Giacomelli F, Vazquez A (2004) Permeability-porosity relationship in RTM for different fiberglass and natural reinforcements. J Compos Mater 38(3) 259-268 Roland C (1913) Possibilities for investment in the manufacture of Canadian flax fiber. Witmipeg Industrial Bureau, Wiimipeg, Canada, 12 pp... 

Isora Fibre A Natural Reinforcement for the Development of High Performance Engineering Materials... 

D. Puglia, J. Biagiotti, and J.M. Kenny, A review on natrual fibre-based composites - part II Application of natural reinforcements in composite materials for automotive industry. 

By embedding natural and near-natural reinforcing fibres (such as flax, cellulose) into a biopolymeric matrix (from cellulose, starch or lactic acid derivatives, thermoplastics as well as thermosets), a new group of fibre reinforced systems are also created, called as biocomposites [28]. 

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