Stimulant medications affect arousal and reward, not attention networks 2025 Kay et al

[Jaybee00]

Highlights​

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Stimulants altered functional connectivity in action regions consistent with arousal
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Stimulants altered functional connectivity in salience regions consistent with reward
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Stimulants did not affect canonical attention networks
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Stimulants reversed the behavioral and brain effects of sleeping less

Summary​

Prescription stimulants (e.g., methylphenidate) are thought to improve attention, but evidence from prior fMRI studies is conflicted. We utilized resting-state fMRI data from the Adolescent Brain Cognitive Development Study (n = 11,875; 8–11 years old) and validated the functional connectivity findings in a precision imaging drug trial with highly sampled (n = 5, 165–210 min each) healthy adults (methylphenidate 40 mg). Stimulant-related connectivity differences in sensorimotor regions matched fMRI patterns of daytime arousal, sleeping longer at night, and norepinephrine transporter expression. Taking stimulants reversed the effects of sleep deprivation on connectivity and school grades. Connectivity was also changed in salience and parietal memory networks, which are important for dopamine-mediated, reward-motivated learning, but not the brain’s attention systems (e.g., dorsal attention network). The combined noradrenergic and dopaminergic effects of stimulants may drive brain organization towards a more wakeful and rewarded configuration, improving task effort and persistence without effects on attention networks.

Graphical abstract​

https://www.cell.com/cell/fulltext/S0092-8674(25)01373-X?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS009286742501373X%3Fshowall%3Dtrue

Not sure I understand this…

 

[rvallee]

Which would mean that ADHD has nothing to do with attention? Arousal is basically wakefulness, which seems to me like it's a part of attention, that both are needed for focus, all of which add up to what we can generally call performance:

Attention is a multifaceted construct that is difficult to operationalize from behavioral studies alone. Performance on attention-demanding tasks is influenced not only by cognitive ability and allocation of attention but also by arousal, vigilance, motivation, effort, and persistence or drive.

All of which makes the behavioral focus of mental health care more and more problematic, and likely a complete dead-end. And since it's almost entirely defined by behavior, well, that would explain why mental health care has barely improved on its own, all the gains have either been socioeconomic adaptations, accommodations, which used to be systematically refused on the "change your behavior" or "just pay attention" model, and drugs that actually target the source of the problem, even if we don't understand how.

Frankly, it seems like behavior tells almost nothing about the underlying problems, and psychiatry is largely built on behavioral observations, most of which wrongly attribute reasons from a third-party subjective that have nothing to do with the actual behavior. The discipline of mental health needs a complete overhaul, so much that starting over entirely from scratch would likely be the single most useful thing it has ever done. But that's never happening, because humans are freaking weird and would rather fail in familiar ways that give the illusion of control than admitting ignorance.