In clinic this morning, a 29-year-old reporting ‘distractibility’ had WAIS-IV Processing Speed Index 79, average Digit Span, and normal Stroop interference, yet he misses handoffs between tasks at work. When you see this brain-behavior pattern, do you attribute the lapses more to slowed perceptual-motor speed or executive control, and which markers (e.g., TMT A/B ratio, intra-individual RT variability) help you decide?