Feeling more awake is not the same as thinking better
Subjective vitality and objective task performance are measured in different ways and can respond differently to the same lighting change. In one controlled study, dynamic lighting (colour temperature shifting between 4000 and 12000 K) significantly improved subjective alertness and response speed compared with static 4000 K lighting, and it also produced faster n-back response times and better MATB-II performance, suggesting positive effects on working memory and executive control [1]. That looks like alignment, but the same study found no significant difference in the P300 brain response or in subjective mood between the two lighting conditions [1]. So even when some performance measures improve, other objective and subjective measures do not move together.
A wider-range colour-temperature study makes the split clearer. As colour temperature rose from 4000 K toward 10000 K, participants' positive mood deteriorated, yet task performance might improve [4]. In other words, the lighting that was better for getting the task done was not the lighting that made people feel better. The researchers concluded that the optimal colour temperature depends on what you are optimizing for — comfort, mood, alertness, or performance — and those optima are not the same [4].
The task and its difficulty decide whether light helps
Lighting effects on performance are not uniform across tasks. In the dynamic-lighting experiment, the effect on cognitive performance depended on how hard the task was, and the benefit showed up in working-memory and executive-control tasks rather than in every measure [1]. A separate study that varied colour temperature across 2700 K, 4000 K, and 6500 K found that 2700 K was associated with enhanced task performance and reduced stress, along with the best thermal comfort ratings [3]. That is a different colour temperature from the one that helped in the dynamic-lighting study, which is a reminder that 'better lighting' is not a single setting.
Task type matters too. In the wide-range study, participants rated their mood more positively during computer tasks than during paper-based tasks, and the researchers examined both computer and paper tasks across the colour-temperature conditions [4]. The practical implication is that a lighting change may help one kind of work and not another, so a general claim that brighter or bluer light improves performance oversimplifies what the experiments actually show.
If you want vitality and performance, you may need to choose
The evidence points toward treating vitality and task performance as separate targets rather than assuming one delivers the other. Dynamic lighting in a windowless workplace improved subjective alertness and some objective performance measures, which supports its use as an environmental intervention for well-being and work output [1]. But the same body of work shows that mood and certain neural measures did not improve [1], and the colour-temperature study found that performance gains could come with worse mood [4].
A narrative review of lighting in industrial and shift-work settings describes dynamic lighting as reducing sleepiness and helping maintain vitality [2], which is consistent with the idea that light can support how people feel. That review does not establish that the same lighting improves objective task performance, and the experimental studies suggest the two can come apart. For a workplace decision, the honest summary is that lighting can be tuned for alertness and comfort or for task output, but the settings that maximize one are not guaranteed to maximize the other [4].
Sources used in this answer
Morning Boost on Alertness, Cognitive Performance and Mood with Dynamic Lighting
Dynamic lighting versus static lighting improved subjective alertness, response speed, n-back response time, and MATB-II performance, with effects depending on task difficulty, but produced no significant difference in P300 or subjective mood.
Lighting in Industrial and Shift-Work Environments and Occupational Health: A Narrative Review
A narrative review reports that dynamic lighting in industrial and shift-work environments reduces sleepiness and helps maintain vitality.
Effects of lighting on task performance, stress and thermal sensation in working environments
At 2700 K, participants reported optimal thermal comfort, which was associated with enhanced task performance and reduced stress levels.
Effects of correlated color temperature of office light on subjective perception, mood and task performance
Increasing colour temperature from 4000 K toward 10000 K was associated with deteriorating positive mood but possibly improved task performance, and the optimal colour temperature varied by demand.
Physical activity as a pathway to thriving at work and job performance among accounting, auditing and finance professionals
Vigorous physical activity was more strongly associated with vitality and thriving was positively associated with task performance, but the study did not examine lighting interventions.