Sunday, June 26, 2016
This is a continuation of my series on a survey I did in 2012, and am only now analyzing the results. To get background information on the subjects and methods of this survey, look at part 1. To look at alexithymia in autism, see part 3. To read about reactions to eye contact, go to part 4, and to read about autistic internal experiences, see part 5. To read about functional language, go to part 6, and lastly, to read about independent living skills, go to part 7.
In this section, I will discuss questionnaire results regarding one area of common coexisting difficulties - executive dysfunction.
Executive dysfunction was assessed using the Frontal Systems Behavior Scale (FrSBe), a 46-item assessment commonly used for adults with neurodegenerative disorders and brain injuries. The questionnaire is normally informant report, but was adapted to self-report by changing the wording of items to first person.
Scores on the FrSBe ranged from 24-93, with a mean of 67.11+/-15.610 (higher scores mean more impairment). Although I couldn't find a cut-off score for this scale, this mean is slightly higher than both pre-Huntington's (mean 59.6) and normal control (mean 54.8) participants in this study, but much lower than participants with a variety of neurological conditions (means from 98.63-140.9) in this study. On balance, this comparison would seem to suggest that the typical participant in my study had mild impairment on this scale, although some were well in the normal range and some had scores typical of individuals with early-stage Alzheimer's disease.
The FrSBe items are divided into three subscales - apathy, disinhibition and executive dysfunction. Apathy items reflect a failure to do activities and a general lack of motivation; disinhibition reflects unusual, socially inappropriate and impulsive behavior; and executive dysfunction reflects disorganization, poor planning and poor self-monitoring.
On the 14-item apathy scale, participants' scores ranged from 11-33, with a mean of 22.66+/-5.439. Compared to the same studies as before, this score is substantially higher than pre-Huntington's (mean 13.7) and normal control (mean 11.7) participants, but lower than the mixed neurological conditions group (means 35.6-48.6). This suggests that many of my participants had mild struggles with apathy and lack of motivation.
On the 15-item disinhibition scale, participants' scores ranged from 6-36, with a mean of 17.85+/-7.313. This score is similar to the pre-Huntington's (mean 13.7) and normal control groups (mean 18.8), and far lower than the mixed neurological group (means 27.4-34.5). This suggests that most of my participants did not have significant difficulty with disinhibition, although the highest scorers had scores similar to neurologically impaired adults.
Lastly, on the 17-item executive dysfunction scale, participants' scores ranged from 6-40, with a mean of 25.8+/-7.115. This score is substantially higher than both pre-Huntington's (mean 19.3) and normal control (mean 24.3) participants, but lower than the mixed neurological conditions group (means 41.3-57.8). This suggests that many of my participants had mild struggles with organization and self-monitoring.
I assessed intercorrelations between the FrSBe subscales and found that executive dysfunction scale was significantly correlated with the other two subscales, which were not correlated with each other. In addition, the FrSBe apathy scale was negatively correlated with age (r = -.376, p = .018), although an ANOVA by three age categories was nonsignificant (p = .068).
There were no significant gender differences, but FrSBe total and executive dysfunction scores were significantly higher in the non-white participants (total p = .018, executive dysfunction p = .006), with FrSBe total means of 65.00+/-15.186 vs 84.25+/-5.500 and executive dysfunction means of 24.81+/-6.675 vs 34.75+/-4.425. However, since there were only 4 non-white participants, this should be replicated with a larger sample size.
Next, I assessed the correlation between AQ and FrSBe. The AQ total score was not significantly correlated with FrSBe total or any of the FrSBe subscales. However, FrSBe total was positively correlated with AQ attention to detail (r = .424, p = .011) and communication (r = .469, p = .004).
AQ communication was also significantly positively correlated with FrSBe disinhibition (r = .339, p = .035) and executive dysfunction (r = .411, p = .010), Meanwhile, AQ attention switching was positively correlated with FrSBe apathy (r = .357, p = .025) and AQ attention to detail was positively correlated with FrSBe executive dysfunction (r = .474, p = .003).