Helping Children Remember Intentions: The Role of the Cue

What the research found

Prospective memory is the ability to remember to carry out an intention at some future moment, and it divides according to what brings the intention back to mind. A clock makes it time-based, as in passing on a message at four o’clock. An object or a situation makes it event-based, as in buying the medicine the next time you pass the pharmacy. The permission slip in the bag and the coat on the peg are both event-based problems.

Forty-seven children in Rome, aged eight to thirteen, were tested on the second kind. Twenty-four had just come to the Bambino Gesù Children’s Hospital for a first diagnosis of ADHD and were taking no medication for it; twenty-three were typically developing children recruited from local schools, matched for age and IQ. Floriana Costanzo and her colleagues published the results in 2021 in the International Journal of Environmental Research and Public Health.

The continuous job was the same throughout. An animal appeared at the centre of a screen for two seconds, and the child pressed one key for a flying animal and another for a non-flying one, over 108 trials. Onto that the researchers layered a standing instruction for 12 further trials: when a particular image appeared, abandon the sorting and press the spacebar.

Four versions of that instruction were given. In one, the trigger was a single dove at the centre of the screen. In the second, any of four animals could serve as the trigger, so four had to be kept in mind at once. In the third, the trigger was a cactus in one of the four corners, away from where the child was already looking. In the fourth, a single central image again, with a correct spacebar press worth 50 points and a missed one costing 20.

Accuracy on the prospective trials averaged 0.85 in the ADHD group against 0.93 in the control group, a difference significant across the task as a whole. The gap was concentrated. With one central trigger, and again under the large reward, the two groups were statistically indistinguishable. The gap opened when four triggers had to be held at once and when the trigger moved to the periphery. Speed behaved differently, with the ADHD group slower on prospective trials throughout, 1126 milliseconds against 1015, and no condition standing apart from the others.

The sorting task degraded in those same two conditions, and only those, the two groups sorting animals with equivalent accuracy everywhere else. Within the ADHD group, accuracy under the large reward matched their own uninterrupted baseline exactly.

What it means for you and your child

A child who can recount the plot of a book in detail and still walks past the bag by the door has a retrospective memory, the store of what has already happened, in working order. What faltered is the return of a plan at the moment the world offers the cue, and that has its own name and its own conditions.

The study specifies the conditions precisely. One distinctive trigger in the place a child is already looking produced no measurable difference between the groups at all. Four triggers did. A trigger in the corner of the visual field did. Difficulty entered with the number of things to be held and with the distance between the cue and the focus of attention.

The design cannot support a claim that prospective memory alone was impaired. The children with ADHD lost accuracy on the sorting task in exactly the two conditions where they lost accuracy on the prospective task, so the two were degraded together, and the authors did not measure working-memory ability separately or adjust one performance for the other. The task was also a laboratory one, with limited resemblance to a morning at home, and two thirds of the ADHD group had a co-occurring learning disorder. Both groups improved under reward, which makes the reward effect a general finding rather than something particular to ADHD.

The parts that hold are narrow and useful. A standing instruction with one cue, placed where the eye already goes, was performed as well by these children as by their peers. Multiplying the cues, or moving them to the edge of attention, drops performance in a way that shows up on a stopwatch and in an error count.

Symptom ratings tracked task performance across the prospective conditions and not at baseline. Only one of those associations survived correction for multiple comparisons, and it was with accuracy on the sorting task, so the tie between symptom severity and forgetting is what the uncorrected pattern indicates rather than what the corrected analysis established.

All this supplies a word. When the school report says careless, or unmotivated, or does not follow through, the more accurate description is that the intention was formed and did not return when the moment came for it. These children met a single central cue as well as their peers did, and that is the narrowest and firmest thing the study found.