I've been wondering if there was such a thing as developing some kind of physical or psychological dependence on things that relieve pain.
You need to be careful about your use of the word pain: opioids are analgesics, they relieve the subjective experience of pain. They're addictive.
Lignocaine is a local anaesthetic: it prevents nociception or the sensory input that indicates the presence of a noxious stimulus. This in turn renders the relief of any pain unnecessary.
More broadly, however, I was going to suggest that people can become addicted to unpleasant things, not because the unpleasant this is pleasant per se, but because the removal of said unpleasantness is relieving.
A little tangential, but may be worth a read: Are nonpharmacological induced rewards related to anhedonia? A study among skydivers
While we often hear about opioid addiction, which is primarily physical,
This is where you've lost me. While opioid dependency is definitely characterised by physical features e.g. withdrawal syndrome, I think it's very inaccurate to consider it purely a "physical" dependency. If this were the case, then following a prolonged period of abstinence, there would be no concern of relapse -- the once dependent individual has no "physical addiction" to opioids to speak of.
If you would like to know the difference between "physical" dependency to opioids and "physical and psychological" dependency to opioids, I would suggest the following treatment schedule:
- Take the OTC medication loperamide, which is an opioid agonist that cannot cross the BBB.
1 week washout
Take heroin every 8 hours for two weeks
1 week washout
Report back if you noticed a difference between heroin and loperamide.
I wonder if someone could psychologically be hooked on using something like Lidocaine to numb every bruise or injury they get just to numb the pain.
Yes, but not for the reasons you are thinking.
Local anaesthetics act locally, and are the functional equivalent of a reversible lesion to the nerves they are acting on. Anything that an individual finds pleasant can become "addicting", but with respect to lignocaine, it's prudent to note that if it were addictive, it would have nothing to do with any action centrally.
I did hear that cocaine was once used as an anaesthetic, but it was also physically addicting.
Cocaine is still used in ENT surgery, as it is an highly effective vasoconstricting agent.
Its addictive properties, however, are largely thought to be limited to the "psychological" space. Yes, I state that in full appreciation for the above regarding physical. This is not to say that an individual does not have "physical symptoms" e.g. tiredness, but that these symptoms have a locus somewhere in the brain.
This makes me wonder if physical withdrawal and hunger cravings are similar.
One concept in neuroscience/neuropsychology is the somatic marker hypothesis by Dimasio, which proposes that our behaviours/decisions are effectively guided by somatic, or physical sensations that are strongly linked to our emotions.
Thus, the body's need for food would instantiate a physiological state of discomfort that drives us behaviourally to seek food.
Likewise, the body's need for more IV heroin, would evince its own set of "somatic markers" likely to guide one's own behaviour towards the acquisition of more intravenous heroin.
The somatic marker hypothesis: A neural theory of economic decision
Modern economic theory ignores the influence of emotions on
decision-making. Emerging neuroscience evidence suggests that sound
and rational decision making, in fact, depends on prior accurate
emotional processing. The somatic marker hypothesis provides a
systems-level neuroanatomical and cognitive framework for
decision-making and its influence by emotion. The key idea of this
hypothesis is that decision-making is a process that is influenced by
marker signals that arise in bioregulatory processes, including those
that express themselves in emotions and feelings. This influence can
occur at multiple levels of operation, some of which occur
consciously, and some of which occur non-consciously. Here we review
studies that confirm various predictions from the hypothesis, and
propose a neural model for economic decision, in which emotions are a
major factor in the interaction between environmental conditions and
human decision processes, with these emotional systems providing
valuable implicit or explicit knowledge for making fast and