The Thought That Costs Attention

Eighteen Medium Piloncito Coins, Second half of the 8th–second half of the 10th century. The Metropolitan Museum of Art, Open Access (CC0).

A bill sits on the table. The thought has one line and repeats it while other work goes on: how will this be paid? It does not shout. It takes a little attention each time, and the work in front gets what is left. KTT counts it as a thought, noticed or not, even when it arrives as a low hum under everything. Research asks whether such a thought costs something measurable. The studies read for this article did not test whether a thought comes first.

The claim

In 2013, Anandi Mani, Sendhil Mullainathan, Eldar Shafir and Jiaying Zhao published two studies in Science. They proposed that poverty-related concerns consume mental resources, leaving less for other tasks. The idea became known as a loss of mental bandwidth.

The first study

In the first study, researchers induced thoughts about finances in shoppers at a New Jersey mall. Participants thought through a financial problem that was either easy or hard to pay for, and then did reasoning and cognitive-control tasks. In the easy case, poorer and richer participants did equally well. In the hard case, poorer participants did worse, and richer participants did not.

The second study

In the second study, researchers tested 464 sugarcane farmers in Tamil Nadu, India. The farmers receive most of their income at one harvest a year, so they are poorer before it and richer after. The same farmers scored worse on the tasks before harvest than after. The authors report that differences in time, nutrition or work effort did not explain it, and neither did stress. They conclude that the concern itself takes up capacity.

The replication

A replication of the design in Colombia, with high school students reading hypothetical scarcity scenarios, did not find that scarcity taxed cognitive or executive functions. The authors stress the importance of replicating in other cultures and settings. That study differs from the original in sample and setting, so it does not settle the question.

What is not known

Whether the thought itself, and not the situation around it, is what takes the attention is not known. The 2013 studies point to concerns. They did not measure the thought.

Whether the cost is large, small or absent in daily life is open. The studies are group averages, and one replication did not find the effect.

Whether other repeating thoughts, such as unfinished tasks or a conflict, cost attention the same way is not tested in these studies. How a thought of this kind behaves in one person is also not shown.