HYBRID EVENT: You can participate in person at Baltimore, Maryland, USA or Virtually from your home or work.

5th Edition of Global Conference on

Addiction Medicine, Behavioral Health and Psychiatry

October 21-23, 2024 | Baltimore, Maryland, USA

GAB 2024

Meera Vaswani

Speaker at Addiction Medicine, Behavioral Health and Psychiatry 2024 - Meera Vaswani
All India Institute of Medical Sciences (AIIMS), India
Title : Neurobiology of addiction


Drug addiction can be considered a chronic brain disease that affects neurotransmission between neuronal circuits, control behaviour, emotion and cognition. It is characterised by an excessive engagement in drug use, unsuccessful attempts in controlling drug intake, an increase in anxiety and emotional pain

The neurobiological basis of drug addiction is supported by advances in neuroimaging studies.  Functional magnetic resonance imaging (fMRI) suggests that various neurotransmitters; dopaminergic, glutamatergic, GABAergic and acetylcholinergic pathways, are significantly involved in addiction, with dopamine playing a key role in mediating reward perception and reward motivated behaviour. Stress is a risk factor in the vulnerability to the initiation and maintenance of drug abuse and relapse in subjects with history of drug abuse. Corticotropin-releasing factor (CRF), a neurotransmitter involved in the stress response, plays an important role in addiction

Substance  abuse dysregulate key brain systems involved in motivation, reward, decision-making and memory. Dopamine, referred as the reward neurotransmitter, has long been considered to play important role in reward pathway  leading to addiction. The mesolimbic dopaminergic  "reward' pathway plays a key role in the pleasurable and positive reinforcing effects of drugs.  Mesolimbic dopaminergic neurones in the ventral tegmental area project to brain regions including the nucleus accumbens and amygdala. GABA-ergic interneurones have key inhibitory or ‘braking’ effect on these dopaminergic neurones. A range of inhibitory receptors, including mu opioid, cannabinoid CB1 and nicotinic, regulate GABA-ergic activity, which in turn modulate the mesolimbic dopaminergic neurones. Activation of inhibitory receptors results in release of endogenous endorphins by alcohol, stimulants, or by consumption of opioids or cannabis, where as the GABA-ergic  inhibition of the dopaminergic neurone is reduced.

As an individual becomes addicted, there is a shift away from this positive reinforcement to the compulsive, habitual drug-seeking behaviours as is seen by cravings or withdrawal symptoms. However, other neurotransmitters such as, endogenous opioid system, are likely to be equally important in pleasure and reward  in drug addiction.

For many drugs of abuse, continual drug use results in tolerance. This is particularly evident for alcohol and opiates, although less so for stimulants. Thus tolerance is driven by neuroadaptive changes in which receptors activated by the drug are downregulated or exhibit reduced sensitivity resulting in  homeostatic imbalance of brain function. Abrupt cessation of the drug results in withdrawal because of non availabilty of drug needed to maintain the homeostatic balance. The exact underpinning neurobiology of tolerance and withdrawal varies because of the range of neurotransmitter systems involved in the pharmacology of various drugs of abuse.

Recent research has highlighted the importance of other neurotransmitters, such as endogenous opioids in reward and addiction. Endogenous opioid receptors consist of three subtypes: mu, kappa and delta. The endogenous agonist at the mu opioid receptor is beta-endorphin, which has euphoric and analgesic effects. Changes in the availability of mu opioid receptors have been demonstrated in alcohol, heroin and cocaine addiction. Kappa opioid receptors are associated with dysphoria, and dynorphin is the endogenous agonist. Thus, mu and kappa have opposite effects, with stimulation of kappa receptors reducing the pleasurable effects associated with mu stimulation. Delta opioid receptors are important in analgesia and have enkephalins as the endogenous agonist. By empowering the audience with knowledge and resources, this presentation aims to foster Neurobiological basis of Addiction

Audience Take Away Notes:

  • This talk would enlighten the audience / researchers in understanding the underpinnings of Neurobiology of Addiction
  • Researchers would understand important role of various neurotransmitters involved in drug addiction
  • How excessive use of drugs, unsuccessful attempts in controlling drug intake results in tolerance and  increase in anxiety and emotional pain


Dr Meera Vaswani, has been a Professor, WHO Collaborative National Drug Dependence Treatment Center, All India Institute of Medical Sciences, New Delhi, India· She is the First Scientist in India to initiate Genomic Pathways in Drug and Alcohol Abuse in Indian population. She has more than 20 years of experience in Addiction Psychiatry and has been recepient of  several awards from NIDA, NIH. Distinguished International Scientist  collaborative award(DISCA),  for which she worked in Louisiana State University Health Sciences  (LSUHS). International visiting faculty award for which she worked at University of Pennsylvania(UPENN), Philadelphia AND   University of Minnesota, Minneapolis in USA. She was One of the Three Scientists to be awarded United Nationas Fellowship for Advanced Training in Substance Abuse for which she worked in University of Scotland, Glasgow, UK . She was invited by Japan to represent India for formulating by laws of Asia Pacific Society for Alcohol and Addiction Research (APSAAR) and was elected as Founder Member on “Board of Directors”. She has Chaired Scientific Sessions on substance/ alcohol abuse in American Psychiatric Association (APA) Meeting (2002-2012). She has been Nominated as Honorary member of “Board of Directors” by Scientific Council of Skibbereen University, UK.