High-imagery Sentences Research Articles

The Impact of Reading Intervention on Brain Responses Underlying Language in Children With Autism.

Deficits in language comprehension have been widely reported in children with autism spectrum disorders (ASD), with behavioral and neuroimaging studies finding increased reliance on visuospatial processing to aid in language comprehension. However, no study to date, has taken advantage of this strength in visuospatial processing to improve language comprehension difficulties in ASD. This study used a translational neuroimaging approach to test the role of a visual imagery-based reading intervention in improving the brain circuitry underlying language processing in children with ASD. Functional magnetic resonance imaging (MRI), in a longitudinal study design, was used to investigate intervention-related change in sentence comprehension, brain activation, and functional connectivity in three groups of participants (age 8-13 years): an experimental group of ASD children (ASD-EXP), a wait-list control group of ASD children (ASD-WLC), and a group of typically developing control children. After intervention, the ASD-EXP group showed significant increase in activity in visual and language areas and right-hemisphere language area homologues, putamen, and thalamus, suggestive of compensatory routes to increase proficiency in reading comprehension. Additionally, ASD children who had the most improvement in reading comprehension after intervention showed greater functional connectivity between left-hemisphere language areas, the middle temporal gyrus and inferior frontal gyrus while reading high imagery sentences. Thus, the findings of this study, which support the principles of dual coding theory [Paivio 2007], suggest the potential of a strength-based reading intervention in changing brain responses and facilitating better reading comprehension in ASD children.

Sentence comprehension in autism: thinking in pictures with decreased functional connectivity

Comprehending high-imagery sentences like The number eight when rotated 90 degrees looks like a pair of eyeglasses involves the participation and integration of several cortical regions. The linguistic content must be processed to determine what is to be mentally imaged, and then the mental image must be evaluated and related to the sentence. A theory of cortical underconnectivity in autism predicts that the interregional collaboration required between linguistic and imaginal processing in this task would be underserved in autism. This functional MRI study examined brain activation in 12 participants with autism and 13 age- and IQ-matched control participants while they processed sentences with either high- or low-imagery content. The analysis of functional connectivity among cortical regions showed that the language and spatial centres in the participants with autism were not as well synchronized as in controls. In addition to the functional connectivity differences, there was also a group difference in activation. In the processing of low-imagery sentences (e.g. Addition, subtraction and multiplication are all math skills), the use of imagery is not essential to comprehension. Nevertheless, the autism group activated parietal and occipital brain regions associated with imagery for comprehending both the low and high-imagery sentences, suggesting that they were using mental imagery in both conditions. In contrast, the control group showed imagery-related activation primarily in the high-imagery condition. The findings provide further evidence of underintegration of language and imagery in autism (and hence expand the understanding of underconnectivity) but also show that people with autism are more reliant on visualization to support language comprehension.

Imagery in sentence comprehension: an fMRI study

This study examined brain activation while participants read or listened to high-imagery sentences like The number eight when rotated 90 degrees looks like a pair of spectacles or low-imagery sentences, and judged them as true or false. The sentence imagery manipulation affected the activation in regions (particularly, the intraparietal sulcus) that activate in other mental imagery tasks, such as mental rotation. Both the auditory and visual presentation experiments indicated activation of the intraparietal sulcus area in the high-imagery condition, suggesting a common neural substrate for language-evoked imagery that is independent of the input modality. In addition to exhibiting greater activation levels during the processing of high-imagery sentences, the left intraparietal sulcus also showed greater functional connectivity in this condition with other cortical regions, particularly language processing regions, regardless of the input modality. The comprehension of abstract, nonimaginal information in low-imagery sentences was accompanied by additional activation in regions in the left superior and middle temporal areas associated with the retrieval and processing of semantic and world knowledge. In addition to exhibiting greater activation levels during the processing of low-imagery sentences, this left temporal region also revealed greater functional connectivity in this condition with other left hemisphere language processing regions and with prefrontal regions, regardless of the input modality. The findings indicate that sentence comprehension can activate additional cortical regions that process information that is not specifically linguistic but varies with the information content of the sentence (such as visual or abstract information). In particular, the left intraparietal sulcus area appears to be centrally involved in processing the visual imagery that a sentence can evoke, while activating in synchrony with some core language processing regions.

Perceptual components of situation models.

These experiments examined the hypothesis that situation model construction involves perceptual processing--specifically, processing that involves visuospatial information. In this research, a dual-task paradigm was used to demonstrate that tasks that engage visuospatial processes interfere more with the generation of a situation model than tasks that are less likely to involve these processes or tasks that are verbal in nature. Using Albrecht and O'Brien's (1993) contradiction effect as evidence of situation model construction, Experiment 1 demonstrated that participants reading short texts while simultaneously holding high-imagery sentences in memory failed to show a significant contradiction effect in comparison with readers holding low-imagery sentences in memory. In Experiment 2, participants reading texts while retaining a difficult visuospatial memory load showed disrupted comprehension in comparison with readers retaining a verbal memory load.

Regional cerebral blood flow patterns related to verification of low- and high-imagery sentences

Although several SPECT studies have shown left inferior occipital activation with visual imagery, the reliability of this finding remains doubtful. The present study replicated two conditions of a previous SPECT-study exploring rCBF in subjects verifying the correctness of low- and high-imagery sentences. As in the previous study, verification of high-imagery sentences was associated with higher flow rates in the left inferior occipital region and lower flow rates in the right anterior frontal region. By contrast, a bilateral increase of thalamic flow rates with imagery was not replicated, and there was a higher flow rate in the left inferior temporal region with low-imagery sentences which had not been found in the original study.

Visual imagery and knowledge about the visual appearance of objects in patients with posterior cerebral artery lesions

The purpose of this study was to explore whether patients with left posterior cerebral artery (PCA) lesions have defective mental visual imagery and to differentiate whether such a deficit stems from a loss of knowledge about the visual appearance of objects or from an inability to create mental visual images out of preserved visual knowledge. Normal controls and patients with either left or right PCA lesions were asked to verify low- and high-imagery sentences and then to verify pictorial representations of the predicates of high-imagery sentences. High-imagery questions concerned either the shape or the color of objects. In addition, perceptual discrimination of shape and color was assessed. Patients with right PCA lesions were impaired on the perceptual discrimination tasks. Left PCA patients did not significantly differ from controls on low-imagery sentences but scored significantly lower on shape and color questions. Their impairment was distinctly more severe with the pictorial than with the verbal versions of shape and color questions. In comparison to patients with occipital left PCA lesions, patients with temporo-occipital left PCA lesions were selectively impaired on verbal and visual color questions. It is concluded that patients with left PCA lesions lack knowledge about shape and color of objects, but that their ability to convert visual knowledge into mental images is preserved.

EEG alpha asymmetries in stutterers and non-stutterers: Effects of linguistic variables on hemispheric processing and fluency

The EEG hemispheric alpha asymmetry technique was used to gather data from anterior and posterior language areas during a resting condition and in a sentence repetition task. Subjects were nine adult stuttering males and nine adult fluent male controls. Sentences were controlled for imagery, syntactic complexity, and rate. Significant within- and between-groups differences were found for both resting and testing conditions. Posteriorly, stutterers showed no differences between resting and testing conditions, while controls showed increased left hemisphere activation. Of the linguistic variables investigated, only imagery was involved in a significant interaction. Fluent males showed greater posterior left hemispheric activation for high and low visual imagery sentences, compared to greater posterior right hemispheric activation in stuttering males. Significantly greater alpha power was found for low vs high imagery sentences in the anterior and posterior left hemisphere sites for both subject groups, and in the right hemisphere sites for the stuttering group only. Fluency data is presented. Differences between groups in alpha power changes from resting to testing conditions are discussed.

Effect of imaging sentences on concurrent unimanual performance

In Experiment 1, 96 right-handers tapped on a telegraph key while concurrently imaging, overtly rehearsing, or silently rehearsing concrete sentences in a between-subjects design. A strategy control problem for men precluded an interpretation of their data but in women, significantly better recall with imagery than rehearsal was accompanied by comparable right-lateralized manual interference in imagery and overt rehearsal and aymmetrical decrement in silent rehearsal. In Experiment 2, overtly rehearsing high imagery sentences produced a trend toward more right-left manual asymmetry in 45 right-handers relative to rehearsing low imagery sentences. The outcomes of these two preliminary studies point toward a role for the left hemisphere in sentence imagery beyond its contribution to sentence processing per se.

Recognition of Sentences by Native and Nonnative Speakers of English: Probing the Role of Imagery

M The study of imagery and underlying comprehension and recognition of verbal information forms foundation stones of cognitive psychology. Research has identified positive effects of mental imagery on recall (Begg & Paivio, 1969; Paivio, 1971, 1977, 1978; Paivio & Begg, 1971). Paivio and Begg (1971), for example, presented abstract and concrete sentences to subjects and found that on a recognition memory task, changes in meaning of concrete, highimagery sentences (e.g., The vicious hound chased a wild animal) were detected more readily than changes in meaning of abstract, lowimagery sentences (e.g., The absolute faith aroused an enduring interest). Previously, Begg and Paivio (1969) had found that subjects noticed a semantic change more easily than a change in sentence structure for concrete, high-imagery sentences than they did for abstract, lowimagery sentences. Evidence indicating that visual imagery is an epiphenomenon which accompanies learning but which has nothing functional to do with it has also been presented (Day & Bellezza, 1983; Pylyshun, 1973, 1981); however, study of mental imagery as a mediator of cognitive tasks continues to be a major concern of cognitive psychologists. Although investigation of role imagery plays in processing of information by nonnative speakers has been virtually ignored in memory research, as Rose (1975) puts it, the bilingual is subject par excellence for investigations of cognitive processes (p. 150). The study reported here yields information concerning role of mental imagery

Imagery effects and semantic similarity in sentence recognition memory.

The idea that subjects often use imagery to discriminate semantically similar sentences was tested in three experiments. In the first experiment, subjects heard subject-verb-object sentences in the context of either a comprehension task or an image-generation task. Their memory for the sentences was tested using a two-alternative forced-choice recognition test in which different types of distractor sentence were used. A sentence semantically similar to the target sentence was one type; a sentence with the same subject and object nouns as the target sentence, but dissimilar in meaning, was another type; and a sentence similar in meaning to one of the stimulus sentences, but not to the target sentence, was a third type. The results showed that the image-generation instructions enhanced later recognition performance, but only for semantically similar test items. A second experiment showed that this finding only holds for high-imagery sentences containing concrete noun concepts. A third experiment demonstrated that the enhanced recognition performance could not be accounted for in terms of a semantic model of test-item discrimination. Collectively, the results were interpreted as providing evidence for the notion that subjects discriminate the semantically similar test items by elaborating the sentence encoding through image processing.

The role of perceptual and semantic elaboration in high- and low-imagery sentence recall

Sentence imagery effects in recall are predicted by both perceptual and semantic elaboration models. The former attributes superior recall of high-imagery sentences to the addition of perceptual network components to an existing semantic network; the latter claims that additions of semantic components are involved. In order to identify the responsible components, free associates were generated to otherwise similar high- and low-imagery sentences in a short-term memory task. In accordance with the perceptual elaboration model, associates differed in rated imagery, but not in number. In a second study, the causal role of perceptual elaboration in recall was investigated by using high- and low-imagery sentence associates as recall cues. Differential effects of cue imagery were found for high-imagery sentences, indicating that perceptual codes are in part responsible for superior high-imagery sentence recall. Evidence is presented that perceptual and semantic network components are involved in a processing trade-off, and the adequacy of present network models to explain it is discussed.

Reading and listening to high and low imagery sentences

Five reaction time experiments were performed to clarify the role that imagery plays in sentence understanding. In the first experiment, subjects had to decide whether visually presented sentences were true or false. Reading and verifying high-imagery sentences took longer than reading and verifying low-imagery sentences. This was true even though both types of sentences were equal in difficulty when auditorily presented. In Experiment 2, the words of each sentence were serially presented in order to make the reading presentation more like the listening presentation. Again, reading interfered more with the processing of high-imagery sentences than low-imagery sentences. Experiments 3 and 4 were identical to Experiments 1 and 2 except that a comprehension task was used instead of a verification task. Again, reading interfered more with the high- than the low-imagery sentences. However, in Experiment 5, when a grammatical judgment task was used, reading no longer interfered more with the high-imagery sentences. These results suggest that imagery plays a significant role in the comprehension of high-imagery sentences.

The verification of high and low imagery sentences.

The verification of high and low imagery sentences.

The role of imagery in the evaluation of sentences

Reaction time was the dependent variable in this sentence verification experiment. Simple sentences, which were either true or false, were constructed such that in some cases it was easy to form an image of the sentence, and in other cases forming an image was difficult. Ss' ratings were employed to select low- and high-imagery sentences. It was found that high-imagery sentences could be verified more rapidly than low-imagery sentences. Instructions which did not mention imagery were given to some Ss while others were specifically asked to employ imagery, but the reaction times of these two groups of Ss did not differ. It was concluded that imagery facilitates the process of sentence verification and that models of this process which restrict themselves to purely semantic operations are incomplete.