Cognitive Loci of Impairments in Picture Naming by Aphasic Subjects

Abstract

In order to identify the process or processes responsible for impaired naming by aphasic patients, ten aphasic adults and ten normal adults performed three independent tasks—picture naming, modified Sternberg picture recognition, and modified Sternberg random shape recognition (Sternberg, 1966). Response times and error percentages were the dependent variables. Independent variables in naming were stimulus codability measured in bits of uncertainty (two levels) and number of naming trials (three trials). Independent variables in the recognition tasks were uncertainty (two levels), number of stimuli to be remembered (two or four stimuli) and response type (“yes” or “no”). The results showed that uncertainty had significant effects on naming but not on recognition performance. The aphasic group produced significantly longer naming response times regardless of uncertainty level. The differences between groups were much greater for high-uncertainty pictures (1100 msec) than for low-uncertainty pictures (270 msec). A comparison of estimates of word retrieval times showed that the two subject groups differed significantly for high-uncertainty but not for low-uncertainty items. It was concluded that (1) use of the term “word retrieval problem” rather than “loss of memory problem” was justified to describe the major component in the aphasic naming impairment for high-uncertainty items, and (2) when naming low-uncertainty items these aphasic subjects did not demonstrate a word retrieval problem. The results indicate that treatment procedures designed to improve naming should be process rather than content oriented.

Referential processing: Reciprocity and correlates of naming and imaging

“…The effect of uncertainty is consistent with prior research by Lachman (1973), and with evidence that uncertainty and response competition disrupt picture naming among aphasics (e.g. , Mills, Knox, Juola, & Salmon, 1979;Rochford & Williams, 1962). At least two theoretical mechanisms could explain why naming slows down as the number of competing responses increases: (1) activation may be less vigorous when diffused over multiple pathways, or (2) competing names may inhibit one another and thereby delay the emergence of a particular response.…”

Object salience and code separation in picture naming

“…The reasoning in both cases is somewhat indirect; however, the conclusions conflict. Bartram's results support the conclusion that update effects do occur in the visual system; the Lachman and Lachman (1980) and Mills et al (1979) data suggest the opposite.…”

“…Because the magnitude of update increases with uncertainty/salience, it appears that the update effect must reside in an uncertainty-sensitive process. Visual processing, however, does not show uncertainty effects (Lachman & Lachman, 1980;Mills, Knox, Juola, & Salmon, 1979). Matching two versions of a picture, without naming, yields reaction times with approximately a zero slope over uncertainty.…”

Teste de nomeação de Boston: desempenho de uma população de São Paulo

“…With regard to the properties of the visual stimuli, some studies suggest that perceptual clarity is an important factor, in the case of illness, such as aphasia as well as in situations of cultural deprivation for lexicon access (Mills et al, 1979). The schooling effect in visual confrontation naming has been revealed by Reis et al (2001) and Petersson et al (2001), who detected a significantly worse performance (both in accuracy and reaction times) on immediate naming of two-dimensional representations of everyday objects, when compared to naming of the actual objects, in a group of illiterate subjects.…”