FEATURES TO CONSIDER WHEN BUYING A VRA SYSTEM FOR YOUR CLINIC
April 26, 2023
The most quintessential feature of a VRA (Visual Reinforcement Audiometry) is that of attracting a child’s attention during a hearing test. Even though that sounds simple and easy to accomplish, flashing lights and vigorous moving objects may attract a child’s attention initially, but may not be able to sustain their interest once the sensational aspect of the stimulus is over. It is common knowledge in physiological psychology that once a specific level of stimulation is reached, it desensitizes stimuli below that level to the subject making it less likely that they will respond in future trials.
The functional design of a VRA system should include a variety of stimuli under the control of the clinician as to the level of stimulation and combination of stimuli used during the testing process. We have always advised starting out the testing process with minimal stimulation necessary to attract the child’s attention thus giving the clinician additional options to vary the variety of stimuli and increase its intensity as needed throughout the test.
The VRA systems of yesteryear were pretty simplistic relying upon a static level of stimulation (on or off) to engage the child and keep them engaged after they have seen the show a number of times. This can be even more challenging with advent of high-definition television, You Tube, play stations and many other hyper stimulating media devices that children can be exposed to in the early years of their life.
This level of stimulation has often begged the question regarding the use of Video images or toy based VRA systems to attract modern day children’s attention in light of the background of electronic media prevalent in their home environments. Most, if not all, children have been exposed to television or computer displays suggesting that the video mode of presentation may have some experiential advantage over traditional toy-based systems-even at a young age?
No definitive study has resolved this question of video verses toy stimulation but many clinicians have developed a preference or criteria for using one type of stimulation over the other depending upon the clinical case. I believe that the “magic” is in the clinician regardless of the equipment utilized in the process but can definitely see some advantages to using both types of stimulation in certain situations.
A video display can portray many different images with bright colors and action movements to attract a child’s attention during the test, but these are essentially similar representations in a two dimensional format. Whereas, the toy-based systems may only offer one toy figure as the focal point of the stimulation, adding lights, sound and movement can vary the perceptions greatly of this reinforcement. There is a distinct difference between physical LED lights illuminating in different patterns around the perimeter of the VRA verses a simulation of lights on the video screen! They are not equal in effect and may serve as varying levels of stimuli rather than everything being a derivation of a video image of some sort?
Although it is obvious, the more options a VRA system offers the clinician to attract and maintain a child’s attention the greater the chances of keeping the child interested and engaged in the conditioning process and obtaining valuable information from the test!
The selection of these various stimulus options is often made on with the wireless remote control. “SMART” remotes offer many features to the clinician in a logical and spacious button layout that is easily recognized at first glance. To many buttons require the operator to scan for the intended button taking time and making the VRA test longer and less effective with the possible outcome of losing the child’s attention in between presentation trials. Remote controls should be laid out symmetrically to address the binaural nature of hearing testing using color and orientation to make it easy for the operator to reflexively operate the right or left side of the VRA system. Utilized LEDs to illuminate the functions selected or to designate various operating modes (All-On Feature) are extremely important features that will aid in the quick selection or changing of testing parameters quickly and confidently while they are in the middle of a test attempting to keep the child’s interest and participation.
When dealing with wireless electronics of any kind, on must be aware of potential interference from other devices operating on the same technology or frequency or in close proximity to the area. Some VRA systems only operate on one method of control such as infra-red or Bluetooth signals. As our electronic environment is filled with more and more wireless operated equipment operating on 2.4Ghz such as WIFI and Bluetooth phones, the methods used to block interference are becoming more and more challenged as the world gets crowed electronically speaking. All methods of wireless transmission are susceptible to unique forms of interference and must be considered particularly when introducing them into an active environment such as a hospital or large clinic where other equipment may be in use and operating at a much higher transmission levels than that of VRA wireless systems.
What’s more, is these electronic environments can change over time making single control systems susceptible to outside interference even though they have been operating successfully previously. To accomplish great immunity to outside interference now and in the future, Pehratek VRA systems have incorporated dual methods of wireless transmission (Both Infra-red and Radio Frequencies) that can be easily converted in the field should a wireless conflict occur.