Effects of memory impairment on discourse

Caspari, Isabelle; Parkinson, Stanley R.

doi:10.1016/s0911-6044(99)00009-3

Cited by 38 publications

(31 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, the task used as working memory measures in Smith et al’s (2003) study and those used in the current study (i.e., Backward Digit Span and Digit Ordering) may have been too simple. Even so, Backward Digit Span has been found to correlate with cohesion, a macrolinguistic measure of discourse production (Hartley & Jensen, 1991), while more complex measures of working memory such as the Daneman and Carpenter Reading Span Task (Daneman & Carpenter, 1980), have failed to correlate with discourse production measures (Caspari & Parkinson, 2000). Thus, consistent significant findings regarding the cognitive foundations of local coherence are lacking in the literature, and more research is needed in this area.…”

Section: Discussionmentioning

confidence: 99%

Discourse coherence and cognition after stroke: A dual task study

Rogalski

Altmann

Plummer

et al. 2010

Journal of Communication Disorders

View full text Add to dashboard Cite

Several researchers have suggested that the maintenance of global coherence (topic maintenance) and local coherence (maintenance between utterances) in discourse requires cognitive resources. This study directly tests this hypothesis by examining the relationship between cognitive variables and coherence in narrative discourse produced by mobility-impaired stroke survivors under single (talking) and dual (talking and walking) task conditions. Although there were no effects of the dual task on coherence, global coherence was significantly disrupted regardless of the single or dual task condition. Moreover, global coherence strongly correlated with cognitive function measures, whereas local coherence did not. Findings are consistent with two interpretations: (1) that global and local coherence may be subserved by different cognitive processes or (2) that maintaining global coherence is a more difficult task and thus will show effects of cognitive impairment before local coherence is impaired. These are both testable hypotheses for future research. Learning outcomes After reading the manuscript, the reader will be able to: (1) understand and differentiate between local and global measures of coherence; (2) discuss the effects of a dual task, walking and talking, on global coherence in a gait-impaired group of stroke survivors; (3) understand why the maintenance of global coherence in discourse might be more cognitively demanding than the maintenance of local coherence.

show abstract

Section: Discussionmentioning

confidence: 99%

Discourse coherence and cognition after stroke: A dual task study

Rogalski

Altmann

Plummer

et al. 2010

Journal of Communication Disorders

View full text Add to dashboard Cite

show abstract

“…The possibility that anterograde amnesia might directly impair narrative constructions about the past or the future has been considered previously (16)(17)(18)(19). Several observations support this idea.…”

Section: Discussionmentioning

confidence: 93%

Autobiographical memory, future imagining, and the medial temporal lobe

Dede

Wixted

Hopkins

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

In two experiments, patients with damage to the medial temporal lobe (MTL) and healthy controls produced detailed autobiographical narratives as they remembered past events (recent and remote) and imagined future events (near and distant). All recent events occurred after the onset of memory impairment. The first experiment aimed to replicate the methods of Race et al.[Race E, Keane MM, Verfaellie M (2011) J Neurosci 31(28):10262-10269]. Transcripts from that study were kindly made available for independent analysis, which largely reproduced the findings from that study. Our patients produced marginally fewer episodic details than controls. Patients from the earlier study were more impaired than our patients. Patients in both groups had difficulty in returning to their narratives after going on tangents, suggesting that anterograde memory impairment may have interfered with narrative construction. In experiment 2, the experimenter used supportive questioning to help keep participants on task and reduce the burden on anterograde memory. This procedure increased the number of details produced by all participants and rescued the performance of our patients for the distant past. Neither of the two patient groups had any special difficulty in producing spatial details. The findings suggest that constructing narratives about the remote past and the future does not depend on MTL structures, except to the extent that anterograde amnesia affects performance. The results further suggest that different findings about the status of autobiographical memory likely depend on differences in the location and extent of brain damage in different patient groups.hippocampus | remote memory | anterograde amnesia E pisodic memory affords the capacity to recollect past events that occurred at a particular time and place (2). In humans, episodic recollection allows for reexperiencing an event through a process of "mental time travel" (3). The hippocampus is known to be important for episodic memory, but its specific contribution is unclear. In one view, the hippocampus is needed for the formation and consolidation of long-term memory for a limited time after learning (4). This view finds support in reports that patients with hippocampal damage were intact at recollecting episodes from early life (and impaired only for more recent time periods) (5-7). Another view holds that episodic memories remain dependent on the hippocampus so long as they persist (8, 9). In support of this idea, patients with hippocampal damage were sometimes impaired at recollecting events from early life (1, 10). A third view follows from the suggestion that the same process that enables recollection of the past is also engaged when imagining the future (11-15). In two studies, patients with hippocampal damage were impaired at imagining new experiences or future events (1, 14, but also see ref.6). This deficit has been proposed to be part of a broader impairment in the ability to construct spatially coherent scenes (15).The present study explored these divergent v...

show abstract

“…Each participant's free recall samples were recorded and later transcribed by a research assistant. Transcriptions were then analyzed to obtain three different measures: (a) number of communication units (C-units;Hughes, McGillivray, & Schmidek, 1997;Loban, 1976), (b) number of words per C-unit (Hughes et al, 1997;Loban, 1976), and (c) number of typetoken ratios (TTRs; Caspari & Parkinson, 2000). Table 1.…”

Section: Methodsmentioning

confidence: 99%

“…TTRs have been used as a measure of lexical and semantic productivity or redundancy (Caspari & Parkinson, 2000;Hess, Ritchie, & Landry, 1984). The TTR is calculated by dividing the number of unique content words produced by the total number of content words produced (e.g., ecosystem said five times, heterotrophy said one time, total words = 6; TTR = 2/6, or .33).…”

Section: Measurementioning

confidence: 99%