More than amnesia: prospective cohort study of an integrated novel assessment of the cognitive and behavioural features of PTA

Abstract Background and Objective: Post-traumatic amnesia (PTA) is an early significant stage of recovery from traumatic brain injury (TBI). Current prospective PTA scales do not assess the full range of PTA symptomatology. This study conducted a novel integrated assessment of cognition and behaviour during PTA. Method: Twenty-four moderate-to-severe TBI participants in PTA and 23 TBI controls emerged from PTA were matched for age, gender, and years of education. All completed PTA measures (Galveston Orientation and Amnesia Test: GOAT, Westmead Post-traumatic Amnesia Scale: WPTAS), a cognitive battery; and behaviour ratings scored by 2 independent raters (informant and staff). Results: Significantly poorer performance was found during PTA for attention, processing speed, delayed verbal free recall and recognition, and visual learning. A large effect size was found for category fluency only. Behaviour ratings were significantly higher during PTA. Five behaviours were rated as high frequency (>50%) by both raters: Inattention, Impulsivity, Sleep Disturbance, Daytime Arousal, and Self-Monitoring. Prospective PTA measures produced significantly different duration estimates from 2 days (GOAT vs. WPTAS 1st day) to 9 days (WPTAS 1st day vs. 3-day). The WPTAS correlated most highly with processing speed and language tasks; whilst the GOAT correlated most highly with language and executive control of verbal memory. Conclusion: New prospective measures are needed that integrate core cognitive and behavioural features are brief, easy to administer, and capable of measuring emergence. The term PTA is a misnomer that requires revision to better accommodate the clinical syndrome.