TESTING DEVICE FOR HYPERACTIVITY IN CHILDREN
Technical Field
The present invention is directed toward a portable, electronic device designed to assess deficits in attention and behavioral inhibition in children and. is useful by clinicians as an aid in the diagnosis of hyperactivity, attention deficit disorders and learning problems.
Background Art The diagnosis of hyperactivity has been a difficult problem and has been primarily very subjectively deter¬ mined by teachers and parents. The objective measurement of hyperactivity has been attempted in the past but has not been readily available to schools and mental health professionals.
For many years mechanical tasks such as the Gardner Steadiness Tester have been used for research purposes. Many of these have not been brought to market primarily because of the extreme expenses involved in assembling the same. For example, the Continuous Performance Task would cost, according to its developer, over $8,000 to build. Consequently, only a handful of these devices exist which are primarily located in research settings.
There are several paper and pencil tests which have been used in the diagnosis of hyperactivity including the Porteus Mazes, the Matching Familiar Figures Test and some subtests of the Wechsler Intelligence Scale for Children-Revised. While some of these tests can dis¬ criminate between hyperactive and nonhyperactive groups, they are also influenced by other factors such as visual scanning abilities and intelligence. Consequently, poor performance on a test such as the Matching Familiar Fig¬ ures Test can indicate either hyperactivity, visual motor deficits, or some combination of these two problems.
There is the obvious risk with such tasks that a child will be mislabeled hyperactive because of a poor per¬ formance due to other learning problems.
Other measures of hyperactivity are questionnaires filled out by parents and/or teachers. As such, they rely on the assessments of potentially biased judges and yield subjective estimates of hyperactivity which are not necessarily based directly on the child's be¬ havior. As clinicians become more conservative in their use of medication and opt more often for cognitive/behav¬ ioral interventions, it becomes essential that assessments be based on a child's actual behavior. Research over the years has shown a clear relationship between hyper¬ activity in a child and his impulsivity. Based on this relationship, Applicant previously developed a device for objectively measuring impulsivity based on a child's actual behavior. This device referred to as "Gordon's Measure of Impulsivity" or the "GMI" is described in the Journal of Abnormal Child Psychology, Vol. 1 , No. 3, 1979, pp. 317-326.
The GMI was a specialized timing device wherein the subject earned points by pressing a response button and waiting a prescribed interval of time before hitting the button again. If the child pressed the response button before the interval response time had elapsed, no points were earned and the timer reset. If the child waited long enough, a response light went on and a point was scored.
Although the GMI has proven to be useful in objective- ly measuring impulsivity, research has shown that this is only one factor in diagnosing hyperactivity. A second factor which has been found to be important is the ability of a child to maintain his attention over a period of time.
Disclosure of Invention
The present invention is designed to be used either alone or as a complement to the impulsivity measuring device described above. The invention is used in assessing the ability of a child to sustain his attention over a period of time. In one embodiment, the device sequential¬ ly displays a plurality of numbers and the child is in¬ structed to push a button each time the number "9" ap¬ pears. The device records each correct response, each time the child omitted a response and each time the child committed an error by pushing the button at an improper time. In a second embodiment, which is intended for older children, the child is instructed to push the button only if a "1" appears and is then immediately followed by a "9". Again, the number of correct responses are recorded as are the number of errors of omission and commission. In both embodiments, the test is divided into three separate time blocks and the child's responses are recorded separately for each block. The delay time between the display of each of the numbers can be adjusted and different delay times can be preprogrammed for each of the three separate time blocks.
Brief Description of Drawing For the purpose of illustrating the invention, there is shown in the accompanying drawing one form which is presently preferred, it being understood that the inven¬ tion is not intended to be limited to the precise arrange¬ ments and instrumentalities shown. Figure 1 is a schematic representation of the testing device in accordance with the present invention, and Figure 2 is a schematic diagram showing a logic circuit useful with the invention.
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Best Mode for Carrying Out the Invention
Referring now to the drawing in detail wherein like reference numerals have been used in the two figures to designate like elements, there is shown in Figure 1 a schematic representation of the testing device in accordance with the principles of the present invention and which is designated generally as 10- The device 10 is intended to be mounted in a small metal housing so that it can be easily and conveniently moved from one place to another. The device is also intended to be total¬ ly self-contained needing only an electrical outlet for its operation.
The heart of the device 10 is a microprocessor 12. The microprocessor includes the necessary timing circuits, logic circuits, signal generating circuits and the like necessary to perform the various functions of the device to be described. One of the functions of the processor 12 is to sequentially generate a plurality of different indicia such as alphanumeric characters. For example, these may be the numbers 0-9. This sequence is preferably preprogrammed into the processor 12 and is preferably not in numerical order. The numbers generated will be displayed on the digital display 14 so as to be readily visible to the child to whom the test is being adminis- tered.
In the preferred embodiment of the invention, 180 digits will be sequentially displayed on the display 14. Each digit will be displayed for .2 seconds. The delay or blanking time between digits, that is, the time when nothing appears on the screen, is preferably .8 seconds. However, this time can be adjusted by the clini¬ cian utilizing the time delay control 16.
Research has also shown that the most accurate results can be obtained when a test is administered utilizing three different time blocks or periods. The microprocessor 12 is capable of recording a child's answers separately for each of the time periods and the time duration for
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each time block or period can be selected by the clinician utilizing the block length selector 18. In the preferred operation of the device, three time periods of 180 seconds each is utilized. It is also possible to select a dif- ferent delay time for each of the time periods if this is desired.
Located at a place on the housing so as to be con¬ venient to the child taking the test is a momentary con¬ tact push-button switch 20. Switch 20 could also be lo- cated at a ■ point remote from the main housing such as a hand held switch which could be connected to the micro¬ processor through a remote cable of several feet in length. The child is instructed to watch the display 14 and to actuate the switch 20 whenever he sees a particular number. In the preferred embodiment of the invention, the number "9" has been chosen. For older children such as those of six years of age and up, the child is in¬ structed to actuate the switch 20 only if he sees a par¬ ticular series of numbers being displayed in display 14. Again, in the preferred embodiment of the invention, the child is told to actuate the switch 20 only if he sees a "9" appear that had been immediately preceded by a "1". Game selector switch 22 determines which of these two tests will be administered to the child. It should be noted that other tests such as the GMI described above may also be preprogrammed into the microprocessor 12 and may be selected utilizing the game selector switch 22.
Each time the child correctly actuates the switch 20 after the proper digit or series of digits is displayed at 14, correct response indicator 24 which will be in a position so as to be visible to the child will let him know that he has answered correctly. The number of correct responses for each block or time period along with the number of incorrect responses will be recorded. A game over indicator 26 which may be either a visual or audible alarm or both will advise the child and clini-
cian when the total time has run out for playing the game.
Figure 2 schematically represents a logic circuit demonstrating the manner in which the microprocessor 12 determines the child's correct and incorrect responses. According to a preset sequence, the number generator 28 will generate the digits 0-9 and each will be indi¬ vidually displayed in the display 14 as described above. When the game is being played in the single digit mode, output line 30 from the number generator 28 will go high whenever the number "9" is displayed at 14 and will remain high until the next digit is displayed. In the series mode described above, the output line 30 will only go high when a "9" appears which was preceded by a "1". Again, line 30 will go low when the next digit is dis¬ played.
When the switch 20 is actuated, a signal appears on line 32 associated therewith. Each of lines 30 and 32 are connected to the inputs of three AND gates 34, 36 and 38. Gate 34 is a standard AND gate. Gate 36, how¬ ever, has an inverted input where line 30 is connected and gate 38 has an inverted input where line 32 is con¬ nected.
The output of each of the AND gates 34, 36 and 38 is connected to the different recording means such as digital counters 40, 42 and 44. Counter 40 is incremented each time there is an output from gate 34 and records or stores the number of correct responses. The output of gate 34 also activates the correct response indicator 24. Counter 42 is connected to the output of gate 36 and stores the number of times that the child commits an error by actuating the switch 20 at the wrong time. Counter 44, connected to the output of gate 38, counts the number of times that the proper digit or sequence of digits was displayed at 14 and the child omitted to actuate the switch 20. Each of the counters 40, 42 and 44 may actually consist of three different counters so
that the responses during each different block or time period can be recorded separately.
The logic circuit works in the following manner. When both lines 30 and 32 are high, i.e. when the child
* 5 actuated switch 20 at the proper time after the "9" had been displayed at 14, an output is generated at gate 34. Gates 36 and 38 will be off since each has an inverted input. If the switch 20 is actuated at an improper time, line 32 will be high but line 30 will be low. Accordingly,
10 gate 34 will be closed as will gate .38. Gate 36 will open since line 30 is connected to an inverted input and counter 42 will be incremented. If switch 20 is not actuated when a "9" appears in the display 14, line 32 will remain low when line 30 goes high. As a result,
15 gates 34 and 36 will be closed because of a .low input thereto and gate 38 will open since line 32, although low, is connected to the inverted input. Accordingly, counter 44 will be incremented indicating an additional error of omission.
20 The present invention may be embodied in other spe¬ cific forms without departing from the spirit or essential attributes thereof and accordingly reference should be made to the appended claims rather than to the foregoing specification as indicating the scope of the invention.
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