Connected speech in transient aphasias after left hemisphere resective surgery.

BACKGROUND: Transient aphasias are common in the first few days after resective surgery to the language-dominant hemisphere. The specific speech and language deficits that occur are related to the location of the surgical site, and may include impairments in fluency, lexical access, repetition, and comprehension. The impact of these transient aphasias on connected speech production has not previously been investigated.

AIMS: The goals of this study were to characterize the nature of connected speech deficits in the immediate post-surgical period, and to determine which deficits resolve completely within 1 month.

METHODS & PROCEDURES: Forty-three patients undergoing resective surgery in the left (language-dominant) hemisphere participated in the study. Brief connected speech samples were obtained before surgery, and at 2-3 days post-surgery. In a subset of 24 patients (all of whom presented with aphasia in the immediate post-surgical period), follow-up samples were also obtained at 1 month post-surgery. The samples were transcribed and coded in CHAT format. Ten connected speech measures were derived from each speech sample, and were then compared by time point.

OUTCOMES & RESULTS: At 2-3 days post surgery, deficits were observed in all 10 connected speech measures in comparison to pre-surgical samples: there were decreases in words per minute, words per utterance, and the use of embedded clauses, and increases in phonological errors, lexical access difficulties, morphosyntactic errors, filled pauses, false starts and retraced sequences. The proportion of closed class words could be perturbed in either direction. At 1 month post-surgery, 8 of the 10 connected speech measures had significantly improved, and all measures reflecting structural features (words per utterance, number of embeddings, morphosyntactic errors, proportion of words that were closed class) were equivalent to the pre-surgical time point. Subtle deficits persisted in some other measures; in particular, there were more phonological errors and lexical access difficulties than at the pre-surgical point.

CONCLUSIONS: Transient aphasias after left hemisphere surgery impacted all aspects of connected speech in the immediate post-surgical period. Most of these deficits were largely or completely resolved by 1 month post surgery, but some subtle impairments persisted.