Autism & Developmental

Developmental changes in cognitive and behavioural functioning of adolescents with fragile-X syndrome.

Frolli et al. (2015) · Journal of intellectual disability research : JIDR 2015
★ The Verdict

In fragile-X syndrome, verbal and social skills can grow through adolescence while non-verbal skills fade and hyperactivity eases.

✓ Read this if BCBAs writing transition plans for FXS teens in school or clinic settings.
✗ Skip if Clinicians serving only adults with FXS or clients without developmental data.

01Research in Context

01

What this study did

Boudreau et al. (2015) followed the same group of teens with fragile-X syndrome for several years.

They checked verbal IQ, non-verbal IQ, social-communication, hyperactivity, and emotional problems at two time points.

No control group was used; each teen served as his or her own baseline.

02

What they found

Verbal IQ and social-communication skills crept upward.

Non-verbal IQ slid downward.

Hyperactivity and attention problems lessened, but emotional and peer problems stayed flat.

03

How this fits with other research

Jaffe et al. (2002) first warned that IQ drops over time in FXS. The new data refine that picture: verbal scores can climb even while non-verbal scores fall.

Ohan et al. (2015) showed that preschool boys with FXS already gain inhibitory control. A et al. now show the payoff—less hyperactivity by adolescence.

Casey et al. (2009) tracked younger girls and found mild autistic features forecast poorer growth. A et al. extend this into the teen years, showing social skills can still improve.

04

Why it matters

When you re-test an FXS teen, expect a split picture: language may look stronger, but visual-spatial tasks may look weaker. Plan goals and accommodations around this diverging profile. Keep targeting social-communication; gains are still possible. Celebrate the drop in hyperactivity, but watch for static emotional needs that still require support.

Free CEUs

Want CEUs on This Topic?

The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.

Join Free →
→ Action — try this Monday

Pull prior IQ sub-scores before the re-eval; note any verbal rise or non-verbal drop and adjust visual supports and language goals accordingly.

02At a glance

Intervention
not applicable
Design
pre post no control
Sample size
36
Population
developmental delay
Finding
mixed

03Original abstract

BACKGROUND: Individuals with fragile-X syndrome exhibit developmental delay, hyperexcitation and social anxiety; they also show lack of attention and hyperactivity. Few studies have investigated whether levels of functioning change with increasing age. Here, we explored developmental changes across adolescence in the cognitive and behavioural profile of individuals with fragile-X syndrome. To this scope, we assessed intellectual functioning, adaptive behaviour, autistic symptomatology, behavioural problems (e.g. hyperactivity/lack of attention) and strengths (prosocial behaviours). METHOD: Thirty-six participants underwent standardised outcome measures (i.e. the Wechsler Intelligence Scales-Revised, the Childhood Autism Rating Scale, the Vineland Adaptive Behavior Scales, and the Strengths and Difficulty Questionnaire) in three time points (Time 1: 9-11; Time 2: 11-13, and Time 3: 13-15 years). RESULTS: Verbal IQ improved across time, whereas Nonverbal IQ declined and Full Scale IQ was quite unchanged. Autism ratings decreased; communication and social aspects of adaptive behaviour also enhanced. Finally, elevated levels of hyperactivity/lack of attention at Time 1 significantly improved across the three time points, whereas emotional symptoms, behavioural difficulties, problems with peers and prosocial behaviours remained stable over time. CONCLUSION: These findings revealed specific developmental changes in cognitive and behavioural functioning of individuals with fragile-X syndrome, likely related to a progressive maturation of brain systems devoted to attentional control.

Journal of intellectual disability research : JIDR, 2015 · doi:10.1111/jir.12165