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Victoria Computerized Adaptation of the
Paced Auditory Serial Addition Task (PASAT)

Based on the original PASAT by Dorothy Gronwall

Adapted by Robert J. McInerney

Purpose and Description

The Paced Auditory Serial Addition Task (PASAT) is a serial-addition task used to assess rate of information processing, sustained attention, and working memory. It was developed in New Zealand in the 1970s by Dorothy Gronwall and colleagues, whose research interests at the time involved comparing attentional abilities between persons who had sustained a concussion and uninjured controls. Gronwall and colleagues demonstrated that persons seemingly fully recovered from a concussion could manifest deficits when their brain was put under sufficient stress.

Like the original version presented on audiocassette, this computerized adaptation delivers a pseudorandom series of 61 numbers from 1 to 9. The participant is instructed to add the numbers in pairs, such that each number is added to the one that immediately precedes it. In other words, the second number is added to the first, the third to the second, the fourth to the third, and so on. The same 61 numbers are presented in four trials that differ only in pace. The PASAT takes about 15-20 minutes to administer if all four trials are given.

How Does The Computerized PASAT Work?

The computerized PASAT delivers the number sequences through your computer's external speakers, in much the same way that the standard audiocassette version delivers the numbers through the speakers of a cassette player. The computerized PASAT does not record participants' responses. A trained examiner must still manually record responses as they are made, using the provided printable record form.

How Accurate is the Timing?

The computerized PASAT uses individual audio data files delivered with millisecond precision. This version is not simply a computerized recording of the audiocassette version.

Has It Been Normed?

No. The computerized PASAT features normative data provided by Stuss, Stethem, and Pelchat (1988), which were based on the audiocassette version of the PASAT. However, in a sample of 60 undergraduate students, McInerney, Strauss, and Wilde (2003 - unpublished raw data) found that this computerized PASAT and Gronwall's audiocassette version produced equivalent results. Further, in the same sample, the computerized PASAT produced results that were equivalent to Stuss et al.'s (1988) normative data. Similarly, Wingenfeld, Holdwick, Davis, and Hunter (1999) found in a sample of 168 college students that performance on a computerized version of the PASAT did not differ significantly from published normative data for audiocassette versions.

Additional normative data for this computerized PASAT may be collected in the future. In the mean time, we believe that this version will yield results equivalent to the audiocassette version from which it was adapted. Based on the research findings outlined above, we believe also that the Stuss et al. (1988) normative data are suitable for the computerized PASAT.

What Does It Sound Like?

Click here to download a sample audio clip (316 KB). This sample is not representative of the computerized PASAT's timing accuracy.

Program Features


Main PASAT Program

Scoring Module

Important Installation Information

When first installed, the PASAT allows you to play only the Introductory trials (one demonstration and two practice trials). The actual test trials, the scoring module, and the record form are disabled. This is a security feature to prevent unauthorized copying and distribution, and to maintain the integrity and security of the PASAT as a neuropsychological test.

To unlock the PASAT's full functionality, the program must be activated with an Activation Code. The Activation Code is sent to you upon receipt of: (1) payment; and (2) a License Code, which is obtained from the PASAT after it is installed. Please see the PASAT's help file for further information.

Please note that the PASAT will operate only on the computer on which it was activated. It will not operate on other computers. To run the PASAT on other computers, you must purchase additional Activation Codes specifically for those computers. These are available to licensed users at a reduced fee.

System Requirements

The PASAT is a Windows program. It will run on Windows XP, 7, and 10. It will not run on a smartphone, tablet, or Mac.


Initial purchase: $195.00 CAD

Additional copies: $95.00 CAD (licensed users only)

Note: The English version of the PASAT is available from the Department of Psychology at the University of Victoria.

The French and Portuguese versions are available directly from me (click here to contact.)


The PASAT installation package includes the following:

*These remain only partly functional until the PASAT is licensed.

English Version French Version Portuguese Version