Individuals with attention deficit and hyperactivity disorder (ADHD) often demonstrate a reduced enthusiasm for tasks requiring a bit of effort. Because of this, people may mistake their actions as signs of laziness, apathy, or incompetence. However, as the actual traits of ADHD are clarified, the line between them and negative personal qualities is becoming more apparent.
Highlighting one aspect of ADHD, researchers from Monash University, Australia, explored the relationship between ADHD and motivation. Trevor Chong et al. posit that their study is the first to address the concept "that ADHD is associated with a deficit in cognitive motivation." While elucidating the effects of amphetamine-based treatments, they identified a fascinating feature of ADHD called "effort sensitivity."
Sometimes conceptualized as a pool from which we draw, we cognitively apply our effort to tasks. The neurotransmitters dopamine and norepinephrine in brain regions like the prefrontal cortex partly determine the volume of our effort pool.
The American Psychiatric Association identifies deficits in motivation as a key characteristic of ADHD. Researchers have long hypothesized that individuals with ADHD have impaired motivation and difficulty allocating effort. This trait would make it less likely those with ADHD would choose to participate in activities perceived to be mentally or physically effortful. Studies probing the aversion to mental and physical effort in ADHD individuals have been surprisingly scarce.
In their highly (scientifically) motivated experiments, Chong et al. assessed the effort ADHD participants allocated to cognitive and physical tasks. The cognitive task involved rapid recognition of a target letter amidst other text, with varying difficulty levels based on the number of non-target letters. The physical effort task required participants to squeeze a hand-held dynamometer to varying degrees.
Lo and behold, the performance of ADHD individuals mirrored those of control group participants. However, in the absence of medication, individuals with ADHD exhibited an aversion to participating in more demanding/effortful tasks across both cognitive and physical domains. They were sensitive to the perceived effort of a task and less willing to dole out effort.
With a method of measuring motivation in hand, Chong et al. examined how motivation changes with the use of popular ADHD drugs. ADHD participants on their typical medication experienced boosts in motivation, which made them just as willing as control groups to engage in challenging tasks. The amphetamine-based gains in motivation occurred for both mental and physical activities.
Attention, motivation, cognition, effort, reward— ADHD is a complex neurodevelopmental condition involving multiple mental elements. These findings highlight the immediate potential of amphetamine-derived neurotransmitters to reduce effort aversion for individuals with ADHD during goal-directed behavior. The results expand past ADHD and shed light on the role of dopamine and norepinephrine in motivation. With a better understanding of how ADHD impacts motivation, it's harder to label people with ADHD with negative traits unfairly.
Sources: Biological Psychiatry, Journal of Neuroscience