Post-traumatic amnesia (PTA) is a transient period of recovery following traumatic brain injury (TBI) characterised by disorientation, amnesia, and cognitive disturbance. Agitation is common during PTA and presents as a barrier to patient outcome. A relationship between cognitive impairment and agitation has been observed. This prospective study aimed to examine the different aspects of cognition associated with agitation.

The sample comprised 82 participants (75.61% male) admitted to an inpatient rehabilitation hospital in PTA. All patients had sustained moderate to extremely severe brain injury as assessed using the Westmead Post-Traumatic Amnesia Scale (WPTAS) (mean duration = 42.30 days, SD = 35.10). Participants were assessed daily using the Agitated Behaviour Scale and WPTAS as part of routine clinical practice during PTA. The Confusion Assessment Protocol was administered two to three times per week until passed criterion was achieved (mean number assessments = 3.13, SD = 3.76). Multilevel mixed modelling was used to investigate the association between aspects of cognition and agitation using performance on items of mental control, orientation, memory free recall, memory recognition, vigilance, and auditory comprehension.

Findings showed that improvement in orientation was significantly associated with lower agitation levels. A nonsignificant trend was observed between improved recognition memory and lower agitation.

Current findings suggest that the presence of disorientation in PTA may interfere with a patient’s ability to understand and engage with the environment, which in turn results in agitated behaviours. Interventions aimed at maximizing orientation may serve to minimize agitation during PTA.

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.

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).

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.

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.