Time of Day Effects on the Performance on the Screening Test of Auditory Processing

The purpose of this study was to determine if any significant relationships existed between time of day and central auditory processing using a screening test of central auditory performance. The study specifically addressed the following research questions: 1. Is there a difference in the scores of morning and evening type individuals on the Filtered Word subtest, the. Auditory Figure-Ground subtest, or the Competing Words subtest of the SCAN? 2. Is there a difference between morning and evening test time for differing types of individuals on the Filtered Word subtest, the Auditory Figure-Ground subvest, or the Competing Words subtest of the SCAN? 3. Are the effects of time of day the same for morning and evening type people on the Filtered Word subtest, the Auditory Figure-Ground subtest, or the Competing Word subtest of the SCAN? Sixty-six college students participated in this study, 50 females and 16 males. The subjects who participated in this study ranged in ages from 18 to 34 years old. The mean age was 20.6 years. In order to clas^iry subjects as morning and/or evening type, Home and Ostberg\u27s Self-Assessment Questionnaire (1976) was used. Thirty-three subjects were selected that were morning-type and thirty-three subjects were evening type. Approximately half of the morning-type individuals were tested in the morning and the other halt were tested in the evening. Likewise, approximately half of the evening type individuals were tested in the morning and the other half were tested in the evening. Prior to testing, each subject had his or her hearing screened to ensure normal hearing sensitivity. Norma! hearing sensitivity was defined as auditory thresholds of equal to or better than 20dBHL at octave intervals from 1000Hz to 4000F\u27_. in addition, middle ear functioning was screened using tympanometry. Individuals who showed normal middle ear mobility and pressure were included in this investigation. After the determination of adequate hearing sensitivity, all subjects were administered the SCAN. The SCAN, a Screening Test for Auditory Processing Disorders (Keith, 1986), was used to assess central auditory processing of the subjects. The SCAN has three subtests: Filtered Words (FW), Auditory Figure-Ground (AFG), and Competing Words (CW), which are designed to screen auditory perceptual abilities of an individual. Descriptive statistics and inferential statistics v/ere used to analyze the data. The following were the results: 1. Significant differences were found on the Filtered Word subtest in the left ear for the main effect of time of day and type of person. In addition significant differences for the effect of test time were found on the total test score for Filtered Word subtest. 2. No significant differences were found for the Auditory Figure Ground subtest. 3. Significant differences were found in the performance of the subjects in the Competing Word subtest for the right ear. Specifically, an interaction between the main effects of time of day and type of person was noted