Reduced N400 semantic priming effects in adult survivors of paediatric and adolescent traumatic brain injury

Electrophysiology reveals cognitive-linguistic alterations after concussion

Language deficits and alterations to the N400 ERP are commonly reported in aphasia and moderate-to-severe traumatic brain injury (TBI), but have seldomly been investigated after mild TBI, such as concussion. In the present study, the N400 was recorded from young adults within 1-month after concussion and matched controls during a sentence processing task. The N400 recorded to semantically incongruent sentence-final words was significantly more negative and with a more anterior distribution in the concussion group than control group. Among the concussion group, a weaker N400 was associated with more concussion symptoms, slower response time, and poorer executive functioning. Multiple regression results showed that concussion occurrence and male gender were independently associated with a more negative N400-effect, whereas symptoms were associated with a weaker N400. These findings provide novel evidence that alterations to lexical-semantic networks may occur after concussion and vary based on individual differences in post-concussion symptoms and cognitive function.

Passive Elaborative Cueing of Retrieval ProcessesFollowing Traumatic Brain Injury

Purpose: Semantic elaboration is a process in which target information is analyzed in relation to content associated in meaning. The goal of the present study was to examine the use of phrasal cues intended to engage elaborative processes theorized to bolster cognitive performance.Methods: Twenty-two individuals with a history of traumatic brain injury (TBI) and twenty-six neurotypical (NT) individuals were studied. Short phrases intended to elicit elaborative encoding were presented prior to the introduction of a prospective memory task and word-stem completions. Phrases embodied one of three conditions: repeated, semantic, or unrelated information. The stem-completion task was presented between each prospective memory task with fixations serving as cues signaling task completion or functioning as distractors. Event-related potentials (ERPs) were captured during the presentation of word-stems. Following the completion of all word-stems, participants were presented with an old/new recognition task.Results: Linear mixed-effects model analyses revealed a significant effect of condition with respect to word retrieval and recognition memory. Captured ERPs revealed neural signatures resembling a P200.Conclusion: Semantic content increased stimulus saliency, facilitated lexical retrieval, and enhanced retention with the latter process revealing use of semantic cues as a more adept rehearsal strategy than repetition.

"Trying to Get a Grip": Language Competence and Self-Reported Satisfaction With Social Relationships Three Decades Post-Childhood Traumatic Brain Injury

OBJECTIVE

(1) To investigate outcomes in language competence and self-reported satisfaction with social relationships in long-term survivors of childhood traumatic brain injury (TBI); and (2) to establish whether language competence contributes to self-reported satisfaction with social relationships decades after sustaining childhood TBI.

PARTICIPANTS

Twelve females and 8 males aged 30 to 55 (mean = 39.80, standard deviation = 7.54) years who sustained a TBI during childhood and were on average 31 years postinjury (standard deviation = 9.69). An additional 20 participants matched for age, sex, handedness, years of education, and socioeconomic status constituted a control group.

MAIN MEASURES

Test of Language Competence-Expanded Edition and the Quality of Life in Brain Injury questionnaire.

RESULTS

Individuals with a history of childhood TBI performed significantly poorer than their non-injured peers on 2 (Ambiguous Sentences and Oral Expression: Recreating Sentences) out of the 4 Test of Language Competence-Expanded Edition subtests used and on the Quality of Life in Brain Injury subscale assessing satisfaction with social relationships. In the TBI group, scores obtained on the Ambiguous Sentences subtest were found to be a significant predictor of satisfaction with social relationships, explaining 25% of the variance observed.

CONCLUSIONS

The implication of high-level language skills to self-reported satisfaction with social relationships many decades post-childhood TBI suggests that ongoing monitoring of emerging language skills and support throughout the school years and into adulthood may be warranted if adult survivors of childhood TBI are to experience satisfying social relationships.