Falling in love with someone who had ADHD many years ago utterly changed my perspective on this question.
In this article I’d like to share what I’ve learnt about the neurobiological basis for ADHD in the emerging science of mapping functional brain networks. Attention is a complex brain activity, and it should be unsurprising to us that variations are present within any complex system.
There are three behavioural processes that are crucial for sustained and purposeful attention: alerting, orienting, and executive function.
For the “alerting” process to be effective we need to be able to detect a stimulus within a noisy background that has relevance to our goals of living.
“Orientation” involves focusing on the stimulus of interest and collecting relevant associations that help us prioritise its importance, i.e, is this a threat to life, or something I can ignore safely if I choose to? These first two processes occur largely outside of our conscious control.
The final process of “executive control” involves consciously sifting this information and refining it in terms of goal-directed decision making, and results in an action that addresses the person’s goals.
These behaviours are thought to be generated and modified by a complex interplay of brain networks: the Default Mode Network - our internal sense of ourselves, the daydreaming mind, as well as the “chattering monkey mind”; the Central Executive Network activated by external demand and goal-directed decision leading to action, and the Salience Network, like a switch that changes our mindset from rumination to action, influenced strongly by arousal level and stimulant substances.
With these models of “attention” as a sequence of behaviours and “attention” arising as an output of multiple brain networks, the features of ADHD thinking start to make more sense.
The variation in the alerting threshold can give rise to the easy switching between boredom and overstimulation, variation in orienting can give rise to the sense that everything is happening at once and is of equivalent importance, and variation in the threshold to switch to executive thinking, can lead to difficulty reaching a decision or acting on it clearly.
It makes sense that a range of things causing increased arousal can activate the salience network and ease the switch to executive function – caffeine, emotional conflict, fear, excitement, and of course the stimulant medications used to treat some people with ADHD.
Live performance, adrenaline seeking sports, and constant seeking of novel experiences are some of the constructive ways people with ADHD can “self medicate” their feelings of boredom or sometimes overwhelming option paralysis.
We’re all familiar with the deficit model of ADHD: difficulty prioritising actions, difficulty timekeeping, difficulty remaining focused on tasks set by others. It’s worth noting that these same drives and traits can also be very positive and fuel creative problem solving, fun, fitness, sociability and excitement to name a few.
It’s likely that as we come to understand brain networks more deeply, what we currently describe as ADHD will prove to be a catchall term for a host of variations in human attention processes.
I hope that by coming to understand these differences as variations rather than “deficits” or “disorders” we will also learn to think more constructively about how we might accommodate the needs of people with these variations in schools, the workplace, and our relationships with one another.