SOLUTIONS TO HRV DRAWBACKS
Increase experimental power in between-subjects research
by an order of magnitude.
Develop a system which allows parallel data collection, rather than
serial data collection.
By necessity, system must be accurate, robust, and cheap enough to
have several duplicates.
System must be run by user, i.e. under diminished experimenter
control, so interface and tasks must be user-friendly.
THE NEW SYSTEM
iOS device (iPod, iPad etc.)
1. Wi-Fi is connected (if not 3G)
2. Participant downloads application from
3. System is connected and automatically
achieves stable baseline
4. Data is collected through app interface
5. Data is sent through phone mail client to
inbox e.g. firstname.lastname@example.org
6. Data is downloaded, coded, and email
account is deleted – which de-identifies
Study 1: Provisionally implement the described system
Compare reliability to:
a) traditional laboratory ECG
b) other dedicated optical psychophysiological system
Study 2: Replicate a broad series of important between-subjects results
n=105 at baseline
Data taken in class, over four days
Data taken a) at baseline, b) during paced breathing, c) during exposure to
positive/negative image sets.
Study 3: Test normal postural positions for equivalence
Compare reliability to traditional laboratory ECG between postures
Tilt (at 30° to horizontal)
Study 4: Mass HR collection in development economics sample
Pilot of n=80-250, then main sample of n=2500-3000
Data taken in Mekelle, Ethiopia as an adjunct to a food aid program
Roughly equivalent to lab system, median margin of error about 3%
6x cheaper than Polar or sports/portable system
50x cheaper than lab equipment
Further possibilities for pulse signal beyond simple HR monitoring
Once developed, not open-source but free. In dev.
Pre-market, but most likely for sale (for not much!) soon.