Webb Therapy Uncategorized Your Brain’s Chemical Toolkit: Making Sense of the Messengers Running the Show

Your Brain’s Chemical Toolkit: Making Sense of the Messengers Running the Show

If you’ve ever heard someone mention dopamine and serotonin in the same breath as endorphins and hormones, you’d be forgiven for thinking they’re all basically the same thing. Toss in words like neurotransmitter, neuromodulator, and neuropeptide, and the whole business starts to feel like a vocabulary test you didn’t study for.

The truth is, even scientists use these terms loosely, and there’s a good reason it feels muddled — a lot of these chemicals are genuinely doing multiple jobs at once. Dopamine, for instance, isn’t just one thing; depending on where it’s released and what it binds to, it can behave like a fast-acting signal, a slow-burning mood tuner, or even a hormone.

Neurotransmitter

The broadest functional term. A chemical released by a neuron that signals to another cell (neuron, muscle, or gland) across a synapse.

  • Acts fast and locally
  • Has a specific receptor on the target cell
  • Examples: glutamate, GABA, acetylcholine, dopamine

Neuromodulator

A chemical that doesn’t directly transmit a signal but instead adjusts the sensitivity or behaviour of neurons — tuning the volume rather than carrying a message.

  • Acts more slowly and broadly (can affect many neurons at once)
  • Often works by modulating how neurotransmitters behave
  • Many neurotransmitters also act as neuromodulators depending on context
  • Examples: dopamine, serotonin, acetylcholine (yes, the same molecules — context dependent)

Neuropeptide

A structural description — these are neurotransmitters/neuromodulators made of short chains of amino acids (peptides).

  • They can act as neurotransmitters OR neuromodulators (or both)
  • Generally act slower and longer than small molecule neurotransmitters
  • Examples: endorphins, oxytocin, substance P, neuropeptide Y

Hormone

A chemical released into the bloodstream to act on distant target cells throughout the body.

  • Your instinct is basically right — they act on receptors, but anywhere in the body the blood reaches, not just at synapses
  • The key difference is distance and delivery method (bloodstream vs. synapse)
  • Examples: cortisol, insulin, testosterone, adrenaline

The overlap (where it gets messy)

MoleculeNeurotransmitterNeuromodulatorNeuropeptideHormone
Dopamine✅✅❌✅ (in some contexts)
Adrenaline✅✅❌✅
Oxytocin✅✅✅✅
Endorphins✅✅✅❌
Glutamate✅❌❌❌
Cortisol❌❌❌✅

The School

Imagine your brain is a busy school.

Neurotransmitters are students passing notes directly to a specific classmate. One sender, one recipient, one clear message — “meet me at the oval at lunch.” Fast, targeted, and the note stops with that one person.

Neuromodulators are the teacher changing the energy of the entire classroom without addressing anyone in particular — dimming the lights, putting on background music, or simply raising an eyebrow. Nobody receives a direct message, but everyone’s behaviour shifts in response. The whole room recalibrates.

Neuropeptides are notes written on Post-it notes. That Post-it could be passed directly to a classmate (neurotransmitter) or stuck to the whiteboard for everyone to read (neuromodulator). Calling something a neuropeptide just tells you what it’s written on — the small, peptide-based format — not how it gets delivered or who reads it.

Hormones are the notes sent home in a student’s bag for their parents. They don’t operate within the classroom at all — they travel a long distance through a completely different system (the bloodstream), and land somewhere far from where they started, triggering a response in a totally different environment.

Simple summary

  • Neuropeptide = what it’s made of (a peptide)
  • Neurotransmitter = what it does (transmits a signal across a synapse)
  • Neuromodulator = how it acts (tunes/modulates neural activity broadly)
  • Hormone = how it travels (via bloodstream to distant targets)

Related Post

Inattentional Blindness: What else are we missing?Inattentional Blindness: What else are we missing?

Inattentional Blindness is the failure to notice an unexpected object in a visual display.

Cognitive Psychology is an approach to understanding human cognition by observing behaviour of people performing cognitive tasks. It is concerned with the internal processes involved in making sense of our environment, and deciding what behaviour to be appropriate. These processes include attention, perception, learning, memory, language, problem-solving, reasoning, and thinking.

Re-write: Distract!

The most famous experiment that shows evidence for inattentional blindness is the Simons and Chabris (1999) experiment where an audience or viewer watches a group of people pass a ball to one another wearing either black or white, and a woman dressed as a gorilla enters the frame for 9 seconds, then walks off. Results reported that 50% of the observers did not notice the gorilla enter the frame. In all honesty, when I saw the video for the first time at university, I did not see the gorilla enter the frame either.

In reality, we are often aware of changes in our visual environment because we detect motion cues accompanying the change. This information suggests that our ability to detect visual changes is not only due to the detection of movement. An obvious explanation of the gorilla experiment findings is that the visual representations we form in our mind are sparse and incomplete because they depend on our limited attentional focus. Simons and Rensick (2005) point out that there are other explanations, such as: detailed and complete representations may exist initially but may either decay rapidly or be overwritten by a subsequent stimulus. It needs to be said that in the gorilla experiment, the observers are instructed to count how many times the ball passes, so really, our attention is deliberately compromised. The real-life implications of inattentional blindness reveals the role of selective attention in human perception. Inattentional blindness represents a consequence of this critical process that allows us to remain focused on important aspects of our world without distraction from seemingly irrelevant objects and events.

Being present, in the moment (mindfulness) can help aid our attention. Distractions such as using our mobile phones, advertising material, other people, “multi-tasking” and internal emotional states all contribute to our lack of focus and attention. Think of a magician’s ability to manipulate their audiences attention in order to prevent them from seeing how a trick is performed. There are also safety implications, as you would know … if you’ve been paying attention, haha.

Just food for thought, my readers, and friends 🙂

Understanding Addiction: A Modern, Integrative PerspectiveUnderstanding Addiction: A Modern, Integrative Perspective

Abstract

Addiction is a complex, multifaceted phenomenon that has been described variously as a disease, disorder, syndrome, obsessive-compulsive behaviour, learned behaviour, or spiritual malady. Modern scientific understanding emphasises addiction as a chronic brain disorder shaped by neurobiological changes, learning, and social context. This article examines each conceptualisation and presents an integrated definition that aligns with current neuroscience, psychological, and public health evidence.

Conceptualising Addiction: Labels and Their Accuracy

No single label fully captures addiction’s complexity; each highlights certain truths while overlooking others.

Disease

From a medical perspective, disease is the closest match. Addiction involves persistent neurobiological changes in reward, stress, and self-control circuits, increases relapse risk over years, and shows substantial genetic vulnerability (~50–60%) (NIDA, 2018; Heilig et al., 2021). Treatments improve outcomes but rarely “cure” the condition. This framing is used by the American Society of Addiction Medicine (ASAM), NIDA, WHO ICD-11, and DSM-5-TR (as “Substance Use Disorder”) (NIDA, 2018).

Disorder

Disorder is also scientifically accurate and slightly less medicalised. DSM-5’s “Substance Use Disorder” captures behavioural, psychological, and biological criteria and recognises functioning and harm rather than framing addiction strictly as a lifelong disease (Heather, n.d.; Heilig et al., 2021).

Syndrome

Addiction may be described as a syndrome because it is a cluster of symptoms with behavioural and physiological manifestations, without a single causative factor. However, the term is too generic for practical use outside clinical texts (Blithikioti et al., 2025).

Obsessive and Compulsive Learned Behaviour

Addiction involves learning, habit formation, and compulsion through reinforcement of rewarding behaviours (Hyman, 2005; Hausotter, 2013). Yet describing it solely as learned behaviour ignores genetic predisposition, neuroadaptation, withdrawal, and social factors.

Spiritual Malady

Some mutual-aid traditions characterise addiction as a spiritual malady. While this may be meaningful for individuals, it is not scientifically explanatory: addiction can be adequately explained via biological, psychological, and social mechanisms (Lewis, 2017).

Modern Integrative Definition

The most accurate contemporary description of addiction is:
“A chronic, relapsing disorder of brain circuits involved in reward, stress, and self-control, shaped by learning, environment, and social context”.

This definition encompasses:

  • Disease/disorder: medical accuracy
  • Learned behaviour and compulsion: neuroscience and behavioural accuracy
  • Social determinants: public health relevance
  • Flexibility for personal or spiritual interpretations

In short, addiction is best understood as a bio-psycho-social condition that is treatable and sometimes reversible, rather than a deterministic, lifelong curse.

Neurobiology: Why Addiction Is Considered a Brain Disorder

Repeated substance use alters structural and functional brain circuits involved in reward, stress, motivation, memory, and self-control (Nwonu et al., 2022; NIDA, 2018). These changes can persist long after use stops, explaining why addiction is more than a matter of “bad habits” or weak will (NIDA, 2025).

Chronicity and Relapse

Addiction is often chronic and relapsing. Even after long periods of abstinence, cues and stressors can trigger relapse (Meurk et al., 2014; SAMHSA, 2023). Key regions implicated include the basal ganglia (habit formation), extended amygdala (stress), and prefrontal cortex (decision-making) (Kirby et al., 2024). Nevertheless, many individuals achieve stable remission, highlighting heterogeneity in clinical outcomes (Heilig et al., 2021).

Learning, Memory, and Habit Formation

Addiction exploits neural mechanisms of learning and memory: rewarding behaviours are repeated and consolidated into habits, with cues triggering compulsive responses even when the substance’s reward diminishes (Hausotter, 2013; Lewis, 2017). This intertwines biological disorder and learned behaviour.

Critiques and Limitations

Some scientists caution that framing addiction strictly as a brain disease is simplistic:

  • Brain changes may resemble those from other motivated behaviours (Lewis, 2017).
  • Many recover without formal treatment (Heilig et al., 2021).
  • Social, environmental, and psychological factors are crucial to understanding addiction (Blithikioti et al., 2025).

Thus, while the disease model is powerful, it does not fully represent addiction’s heterogeneity or socio-psychological dimensions.

Implications for Treatment

Addiction is treatable, not simply curable. Interventions combining pharmacological and behavioural approaches, alongside social support, can foster long-term recovery (Liu & Li, 2018; Heilig et al., 2021). Like other chronic conditions, management — rather than elimination — is often the realistic goal (NIDA, 2018). Neural circuits can gradually readjust, particularly when environmental and personal factors support recovery.

Conclusion

Addiction is a learned, compulsive brain disorder with chronic potential, shaped by neurobiological, psychological, social, and environmental factors. Recognising addiction as both a disorder and a behavioural learning condition avoids extremes: it is neither an unchangeable fate nor merely a moral failing. This integrated perspective supports nuanced understanding, compassionate care, and effective treatment strategies.


References

Blithikioti, C., Fried, E. I., Albanese, E., Field, M., & Cristea, I. A. (2025). Reevaluating the brain disease model of addiction. The Lancet Psychiatry, 12(6), 469–474. https://doi.org/10.1016/S2215-0366(25)00060-4

Hausotter, W. (2013). Neuroscience and understanding addiction. Addiction Technology Transfer Center (ATTC) Network. https://attcnetwork.org/neuroscience-and-understanding-addiction

Heather, N. (n.d.). What’s wrong with the brain disease model of addiction (BDMA)? Addiction Theory Network. https://addictiontheorynetwork.org/brain-disease-model-of-addiction

Heilig, M., MacKillop, J., Martinez, D., Rehm, J., Leggio, L., & Vanderschuren, L. J. M. J. (2021). Addiction as a brain disease revised: Why it still matters, and the need for consilience. Neuropsychopharmacology, 46(10), 1715–1723. https://doi.org/10.1038/s41386-020-00950-y

Hyman, S. E. (2005). Addiction: A disease of learning and memory. The American Journal of Psychiatry, 162(8), 1414–1422. https://doi.org/10.1176/appi.ajp.162.8.1414

Kirby, E. D., Glenn, M. J., Sandstrom, N. J., & Williams, C. L. (2024). Neurobiology of addiction (Section 14.5). In Introduction to Behavioral Neuroscience. OpenStax. https://socialsci.libretexts.org/…/14.05:_Neurobiology_of_Addiction

Leshner, A. I. (1997). Addiction is a brain disease, and it matters. Science, 278(5335), 45–47. https://doi.org/10.1126/science.278.5335.45

Lewis, M. (2017). Addiction and the brain: Development, not disease. Neuroethics, 10(1), 7–18. https://doi.org/10.1007/s12152-016-9293-4

Liu, J. F., & Li, J. X. (2018). Drug addiction: A curable mental disorder? Acta Pharmacologica Sinica, 39(12), 1823–1829. https://doi.org/10.1038/s41401-018-0180-x

Meurk, C., Carter, A., Partridge, B., Lucke, J., & Hall, W. (2014). How is acceptance of the brain disease model of addiction related to Australians’ attitudes towards addicted individuals and treatments for addiction? BMC Psychiatry, 14, 373. https://doi.org/10.1186/s12888-014-0373-x

National Institute on Drug Abuse. (2018). Drugs, brains, and behavior: The science of addiction (Rev. ed.). https://irp.nida.nih.gov/…/NIDA_DrugsBrainsAddiction

Nwonu, C. N. S., Nwonu, P. C., & Ude, R. A. (2022). Neurobiological underpinnings in drug addiction. West African Journal of Medicine, 39(6), 874–884. https://pubmed.ncbi.nlm.nih.gov/36063103

Substance Abuse and Mental Health Services Administration. (2023). What is substance use disorder? U.S. Department of Health and Human Services. https://www.samhsa.gov/substance-use/what-is-sud

Fear and Love, with Tara BrachFear and Love, with Tara Brach

I strongly encourage viewers, readers, and interested friends to visit Tara’s website Tara Brach – Meditation, Psychologist, Author, Teacher. So much of what I consider to be true and helpful is the wisdom I have learned from Tara Brach, an American psychologist, author, and proponent of Buddhist meditation – but more than that, she is authentic, compassionate and honest.