Attention span of humans is probably 8½ minutes

If you think it’s hot now, just wait 8½ minutes. That’s about how long it takes the energy of the sun to reach our planet. Since we are in the shade of the sun all night, we should see heat increase incrementally from sun-up to sundown in about 8½ -minute intervals. 

Of course, it doesn’t happen like that. The sun’s energy is dissipated in many ways so that it feels like a smooth and steady transition of heat. Still, light travels at a specific speed. And the distance from the sun to earth is a specific distance. So, the truth is our days should be divided into segments of eight and a half minutes. 

This brings me to my hypothesis, that 8½ minutes is probably the natural attention span of humans. After all, we’re supposed to have evolved beneath the sun and in so doing adapted to its natural cycle. There is indirect evidence for this theory. 

In 12 hours of daylight, there are 720 minutes. Divided by eight-and-a-half-minute attention spans, that would give us 84.70588235294118 periods a day during which we can concentrate.

Of course, that would round up to about 85, so there is some room for individual variation. 

Did I mention the Perseid meteor shower is this month?

Anyway, theoretically, that means that we probably get distracted about every 8½ minutes. If you find you can’t concentrate for 8½ minutes, then you probably have attention deficit disorder.

Could this be a new diagnostic tool for this deadly malady? Such a tool would even allow for ranking the diagnosis by severity. 

It would work on a reverse scale. Those who can concentrate for 8½ minutes would not have ADD, and those who could only manage 7 minutes would be in stage one. Gauging numbers based on 8½ time increments would be awkward so I’m dropping the one half. 

Oh, look! A Fermi Bubble.

Where was I? Oh, yes. Did you think it was just an accident that television episodes are generally less than 15 minutes long, less than two attention spans? This indicates that the important part of the hour is the two attention spans devoted to advertising. Admittedly most ads are far shorter than an entire attention span.

Do you suppose advertisers know something?

Did you know the dog days of summer are named after the constellation Canis Major and the star Sirius which can be observed this time of year? 

Anyway, when we ask students to sit and pay attention for 50 minutes’ class time, we are asking them to concentrate for six times the evolved attention span for humans. Of course, the 8½-minute number is only for self-disciplined adults who have been highly trained through the public schools. 

It is well known that children can pay attention to things they are interested in for much longer periods of time.

But being interested in whatever they might be interested in must be drummed out of them before they can become productively employed to be interested in something someone else is interested in.

Hey, have you heard about the eclipse this August? My son says there are no hotel rooms left in Boise! 

I think a lot of the concern over “attention deficits” is not about our ability to pay attention. It’s more often over what we pay attention to.

For example, I might be paying attention to my new experiment when my wife thinks I should be paying attention to refinishing the cabinets. 

I must admit there is no evidence to support my theory. And I am going on the word of physicists about how long it takes for the sun’s energy to get here. But good science begins with a theory to try and disprove.

Let’s see if anyone can concentrate on this column long enough to collect some data. 

Gary McCallister, .(JavaScript must be enabled to view this email address), is a professor emeritus of biological sciences at Colorado Mesa University.

NameDivPE Last Chg YTD%Chg

Airgas N/A N/A 142.95 +.00 +.00

AlgntAir 2.80 12.33 128.50 +2.95 +2.30

ArchCoal 1.40 1.05 74.57 +1.04 +1.39

BBarrett N/A N/A 3.17 +.33 +10.41

BP PLC 2.40 31.70 36.14 +.19 +.53

CBRL Grp 4.80 18.55 153.24 -.19 -.12

Chevron 4.32 35.70 109.43 +.68 +.62

ChoiceHtls .86 23.15 62.10 +.55 +.89

Cimarex .32 N/A 92.89 +1.11 +1.19

DowChem 1.84 27.46 63.43 +.68 +1.07

EnCana .06 11.60 9.38 +.35 +3.73

Halbrtn .72 N/A 42.03 -.04 -.10

Harsco .00 N/A 16.60 +.15 +.90

HewlettP .53 13.70 19.36 +.01 +.05

HonwlIntl 2.66 21.71 139.56 +.48 +.34

Kroger .50 14.53 24.06 +.07 +.29

LockhdM 7.28 17.23 295.82 +1.18 +.40

NewmtM .30 N/A 36.59 -.44 -1.20

MolCoorB 1.64 9.04 90.87 -.36 -.40

NL Inds .00 13.82 7.35 +.00 +.00

Safeway N/A N/A N/A +0 +0

Startek .00 92.44 12.47 -.36 -2.89

ThermoFis .60 30.72 175.74 +.59 +.34

US Bancrp 1.12 16.05 52.68 +.44 +.84

UtahMed 1.06 20.79 68.55 +3.95 +5.76

VailRsrt 4.21 41.59 212.72 +.96 +.45

WellsFargo 1.56 13.01 53.40 -.56 -1.05

WmsCos 1.20 2065.33 31.06 -.08 -.26

XcelEngy 1.44 21.18 48.11 -.14 -.29

ZionBcp .48 18.37 45.49 +.63 +1.38



Friday ±Change


Light crude oil 49.52 -0.06

Heating oil 1.64unchg

Natural gas 2.78unchg

Unleaded gas 1.64unchg

  Prices are futures from the New York Mercantile Exchange.


Lean hogs 65.75-0.65

Live cattle 1.14unchg

Feeder cattle 1.51unchg

Corn (bu.) 3.82 +0.01

Soybeans (bu.) 9.57 +0.01

K.C. wheat (bu.) 4.60-.25

  Prices are futures from the Chicago Mercantile Exchange except Kansas City wheat.


The markets this week


Dow Jones

22,092.81 (+262.50, or 1.2%)


Standard & Poors

2,476.83 (+4.73, or 0.2%)



6,351.56 (-23.11, or 0.4%)


Commenting is not available in this channel entry.

Search More Jobs

734 S. Seventh St.
Grand Junction, CO 81501
970-242-5050; M-F 8:00 - 5:00
Subscribe to print edition
eTear Sheets/ePayments

© 2017 Grand Junction Media, Inc.
By using this site you agree to the Visitor Agreement and the Privacy Policy