Selecting Data Acquisition & Analysis Systems for Psychophysiological Research

Considerations in Selecting Data Acquisition & Analysis Systems for Psychophysiological Research

By Joseph Aditi, Ph.D.

Print friendly version: Selecting Psychophysiological Data Systems

Introduction

In 2017, only 20.51% of the total applicants for National Institute of Health (NIH) grants received funding. The
scarcity of new grant funding has sharpened the focus on managing laboratory expenses wisely. Researchers
operating on a small budget are becoming more cautious when it comes to investing in instruments; in
particular, data acquisition and analysis systems.

The decision to procure a data acquisition and analysis system requires careful consideration of a number of
criteria. This can complicate the decision making process, leaving many researchers flustered. New
psychophysiology researchers have expressed the need for a ‘cheat sheet’ to choose such a system.
We asked experienced psychophysiology researchers, who have successfully invested in data acquisition and
analysis systems for their labs, to share their experiences and insights. The focus of this article is to outline six
major considerations that were subsequently identified, namely: research requirements, cost, processing
capabilities, compatibility, after-sales service, and the extent of usage.

1. Meeting Research Requirements

The system must meet not only current research requirements but also those that arise in the near future.
Therefore, it is useful for researchers to carefully identify in advance the physiological variables of interest and
the level of detail required in the data to be collected. Additional factors that need consideration include: the
type of subjects (humans/animals), the number of subjects (single/multiple), the data collection environment
(in-lab/natural environments), the duration of collection, the interaction between the equipment and the
subjects (e.g., will subject reminders, voice notes, etc., be required for extended experiments outside the lab?),
and the extent to which subjects require freedom of movement and comfort. (Wired or wireless?)
It is also helpful to envision the longer term use of the system, e.g., single-project use versus multipleexperiment
use, modular, expandable platforms versus highly-specialized platforms, etc. Once the research
requirements have been established and a candidate set of systems shortlisted, it can be useful to understand
how the system functions (for example, through a pre-sales demonstration) before making a purchase
decision.

Early in his career, Dr. Tony Buchanan (Director of the Cognitive Neuroscience of Stress laboratory at St.
Louis University, Montana), had faced the challenge of purchasing a system that was flexible enough to cover
a range of requirements. Dr. Buchanan observes that some stress studies in his laboratory measure variables
such as heart rate, which is recorded for many minutes, whereas other studies focus on variables such as skin
conductance response, which is measured over seconds or even milliseconds. Thus, a candidate system must
address not only different psychophysiological variables, but also a wide range of acquisition durations.
He additionally requires the system to be user friendly so that students, who may not have had prior training,
can use it with ease. Dr. Buchanan also points out, rightly, that analysis costs are recurrent for some
physiological variables such as assays or hormonal analyses. Unlike those measures, however, a well set up
system is a one-time investment that can serve the laboratory for the life of the equipment.
In summary, he advises that researchers seeking to purchase a data acquisition system be cognizant of the
longer-term benefits, and that they make a cost-effective choice, given the constraints of a finite budget.

2. Instrument Cost

Often, instrument cost tends to be the single most important consideration when procuring a system. Research
grants may allow for only a certain amount to be spent in instrument purchase and it is, therefore, important
that the system proposed in the grant fits within the overall budget.

Besides the cost of the instrument, funds also need to be allocated for purchasing supplies. For instance, the
cost of sensor electrodes can quickly add up, and therefore ought to be considered in the budget. Furthermore,
it is preferable to purchase a system that incurs fewer recurrent/miscellaneous expenses, and that has low
repair/maintenance costs. Those, in turn, can minimize the total equipment lifecycle cost. Some researchers
share costs by developing one core laboratory facility. A modular or multi-user system can thus allow
researchers to share the costs, and thereby meet their grant budget.

Dr. Rob Potter, Director of the Institute of Communication Research at Indiana University, Indiana, has
employed psychophysiology measures in media effectiveness research for more than 20 years. During his
early career, Dr. Potter’s research required collecting data from children playing video games at their school.
Here, portability was among the primary requirements. Another crucial and long term consideration was
affordability. Dr. Potter opted for a modular system capable of extending his system with modules that could be
purchased as the need arose, or when funding became available. Now, when his colleagues express an
interest in conducting research involving new psychophysiology variables such as respiration rate, that module
(i.e., the respiration module) can be purchased within their limited budget.

3. Data Processing Capabilities

Considering the data processing capabilities of a data acquisition and analysis system before procurement is
crucial. Some systems may have an built-in data processing capability, whereas others may need additional
software. If neither is available, open source options (e.g., scripts/programs written using R, or other
programming languages), or a network of users that share data processing programs may be required.
According to Dr. Potter, data processing software that possessed an intuitive, easy-to-use interface along with
the capability to develop and run batch processing scripts was an important system selection criterion. He
appreciates that ‘point and click’ software is user friendly and can lower the barrier to entry in
psychophysiology research; however, his work also needed a continued use of scripts from his legacy “DOS
prompt” software.

When asked what advice he has concerning a data acquisition and analysis system, Dr. Potter says, “Have
people you can call upon. Choose a system that has a network of users, not just affordable. Also, go for a
company that has good (software) documentation.”

4. Interoperability and Compatibility Requirements

It is important to consider both interoperability and compatibility before finalizing data acquisition system
purchases.

In some experiments, subjects may require external stimuli (e.g., visual/auditory,) that are generated by
separate stimulus software. Moreover, when subject responses are acquired and recorded, stimulus marking
(e.g., epochs) may be additionally required. For smooth data collection and analysis, the data acquisition
system may be required to interoperate with such stimulus/marking software. If other techniques are used,
compatibility with the corresponding instruments (e.g., imaging equipment) also needs to be ascertained in
advance. Moreover, depending on the computing infrastructure available, the system may need to be
compatible with different hardware, (e.g., Apple Mac) and software (e.g., operating systems).

At the Kinesiology Department, California State University, Fresno, Dr. Jacobo Morales’ laboratory used a data
acquisition system primarily to train graduate students. Dr. Morales, who has been investigating muscle
physiology during exercise for more than 18 years, advises new researchers, “… get the tools that will allow
you to answer the questions of your line of research. If choices are available, like I said before, [sic] …
precision, resolution, durability, Mac compatibility, customer support.”

5. After-sales Services

After-sales service and/or customer support has been highlighted time and again by expert researchers as
another key factor in the decision to purchase a data acquisition system. Usually, a good quality system serves
a laboratory for several years, during which it may require periodic service or upgrades to maintain quality.
Before procurement, it can be beneficial to ask other users about their experiences regarding after-sales
service and/or customer support. Additionally, while purchasing the system, the terms of sales and post-sales
services should be read carefully, since some vendors may not provide the latter without a separate service
contract. In that case, those expenses should be additionally budgeted and the terms of the contract clearly
understood prior to purchase. Making an informed decision regarding the after-sales service contract helps to
keep the data acquisition system and the laboratory functioning smoothly.

6. Widespread Usage

Citations or reviews may additionally facilitate the decision to purchase a system. A literature search to identify
papers that have utilized the data acquisition platform under consideration is usually helpful. Data acquisition
and analysis systems that have numerous citations in the scientific literature are likely to collect data in a form
that can be shared, and be compatible with other related instruments and/or software. Along with a literature
search, information from collaborators or colleagues who use the same system may also prove useful.

Conclusion

Each physiology laboratory approach particular research problems with specific goals. Identifying a data
acquisition and analysis system that meets the associated requirements can be crucial toward ensuring
research success. The decision to procure a data acquisition system can be complex but need not be
intimidating, especially when applying the six criteria outlined above. Dr. Tony Buchanan, from St. Louis
University, Montana, offers sage advice to help new researchers succeed, “Think broadly, think out a few years
ahead, and think in terms of collaboration.” That applies just as well to the choice of a data acquisition and
analysis system.

References: https://report.nih.gov/fundingfacts/fundingfacts.aspx

Print friendly version: Selecting Psychophysiological Data Systems

BIOPAC life science research data acquisition and analysis systems have been cited in over 50,900 scientific articles and studies and are researchers’ tools of choice across the globe. To further enable researchers in their quest for discovery, BIOPAC presents this series of articles designed to empower researchers in obtaining research funding.