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Magnitude Effect

This is an fMRI study of the magnitude effect in intertemporal choice, which refers to the phenomenon that people become more patient as the magnitude of all of their options increases. We scanned participants in 2 blocked sessions each of low and high magnitude decisions. The study was conducted at two different sites with different scanners and data acquisition specifications.

Task Instruction video 

Task video 


001 temporal discounting task


  • Samuel M. McClure
  • Jonathan D. Cohen
  • Gökhan Aydogan
  • Anthony Liatsis
  • Bokyung Kim
  • Ian C. Ballard

Contact Information:

Name: Ian C. Ballard

Acknowledgements and Funding:

This work was supported by NIA grant R01 031310 (JDC) and NSF grant 1358507 (SMM). We thank Matt Samberg for help with fMRI data collection, and George Loewenstein and Wouter van den Bos for useful comments.

Sample Size:


Scanner Type:

Siemans Allegra 3T and GE Discovery 3T



Accession Number:


How to cite this dataset:

In addition to any citation requirements in the dataset summary please use the following to cite this dataset:

This data was obtained from the OpenfMRI database. Its accession number is ds000223



Warning: some of NIFTI files included in this dataset are missing orientation information (sform and qform). Distinguishing between left and right might not be possible. We are looking into fixing this issue.
More information can be found here:

Browse Data For All Revisions on S3

Direct Links to data:

Revision: 2.0.0 Date Set: Oct. 6, 2017, 11:12 p.m.


- Added orientation warning to readme

Revision: 1.0.0 Date Set: May 3, 2017, 11:18 p.m.


-- Initial Release