Memorize the digits, then solve the task:
🟦 Blue: Lower or Higher than previous number?
🟥 Red: Even or Odd?
Then recall the digits in reverse order.
Memorize...
Remember this number
🔄 Enter in reverse
Shown:
Answer:
Yours:
Streak: 0 | Level: 3
Dual-Task Reverse combines backward digit span with a secondary task performed in parallel. Beyond the reversal demand of Reverse Digits, running a second process simultaneously loads the attentional resource-splitting functions of working memory.
Unlike a single-task reversal, performing two processes at once requires controlling how limited attentional resources are allocated between them. This "dividing and switching of attention" is considered a function particularly related to executive control within the central executive.
The dual-task paradigm is a widely used method in cognitive psychology for investigating working memory processing capacity and executive function. Cognitive limits that remain hidden in a single task can surface when two tasks are performed simultaneously.
In the Baddeley and Hitch model, the central executive is responsible for allocating, switching, and monitoring attention. Dual-task conditions are structured to place especially high load on this function. The cognitive demands parallel everyday situations — taking notes during a conversation, listening to a lecture while writing — where multiple information streams must be processed concurrently.
We recommend becoming comfortable with Reverse Digits before attempting Dual-Task Reverse. Start at a span length where you make few errors on the single task. Under dual-task conditions, accuracy typically drops compared to single-task performance — this is a normal and expected pattern. Sustaining practice at 50–70 % accuracy provides a reasonable level of continued load.
Consciously deciding which task to prioritise as you work may help focus the training on attentional control itself.
Dual-Task Reverse is the task in the TOMOY series that focuses specifically on divided attention. After mastering backward span with Reverse Digits, it raises the load along the axis of simultaneity rather than processing type. Combined with Filtered Digits (inhibitory control) or Transform Digits (all three executive functions), it allows sustained load on distinct aspects of executive function.