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Andreas Roepstorff

Publications and source records attributed to Andreas Roepstorff.

8 recordsLinked to original sources
PubMed2006

Parallel memory systems for talking about location and age in precuneus, caudate and Broca's region.

Language comprehension relies on processing of context. Working memory (WM) evoked by linguistic cues for spatial and nonspatial aspects of a visual scene was investigated by correlating fMRI BOLD signal (or 'activation') with reaction times (RTs). Subjects were asked to indicate either the relative positions or ages of people or objects (referenced by the personal pronouns "he/she/it") in a previously shown image. Good performers of a particular task showed shorter RTs than poor performers. Task-specific activation that is greater in good performers than poor ones is taken to indicate involvement of a given region in performance of the task. Our results indicate that dorsoposterior precuneus supports spatial WM during linguistic processing while a network of areas including the caudate support nonspatial WM in categorization of age. We argue that within-subjects variation of RTs across trials reflects effort. Good performers have higher activity in precuneus as a function of effort compared to poor performers during the spatial task, whereas the opposite is found for the nonspatial task, providing further evidence for specifically spatial WM in dorsoposterior precuneus. Task-independent performance-related modulations of activity were found in Broca's area and amygdala. Broca's area activity increased with effort in both tasks, with a greater increase in good performers than in poor performers, consistent with the region's general role in verbal WM. By contrast, activation in amygdala decreased with effort, with a greater decrease in good performers. We take this deactivation to reflect performance-mediating emotional control. These findings indicate that multiple parallel memory systems are available during language processing, appropriate for different tasks, with performance reflecting which system is selected trial-by-trial and subject-by-subject.

Adult↗
PubMed2005

Motion verb sentences activate left posterior middle temporal cortex despite static context.

The left posterior middle temporal region, anterior to V5/MT, has been shown to be responsive both to images with implied motion, to simulated motion, and to motion verbs. In this study, we investigated whether sentence context alters the response of the left posterior middle temporal region. 'Fictive motion' sentences are sentences in which an inanimate subject noun, semantically incapable of self movement, is coupled with a motion verb, yielding an apparent semantic contradiction (e.g. 'The path comes into the garden.'). However, this context yields no less activation in the left posterior middle temporal region than sentences in which the motion can be applied to the subject noun. We speculate that the left posterior middle temporal region activity in fictive motion sentences reflects the fact that the hearer applies motion to the depicted scenario by scanning it egocentrically.

Acoustic Stimulation↗
PubMed2005

To musicians, the message is in the meter pre-attentive neuronal responses to incongruent rhythm are left-lateralized in musicians.

Musicians exchange non-verbal cues as messages when they play together. This is particularly true in music with a sketchy outline. Jazz musicians receive and interpret the cues when performance parts from a regular pattern of rhythm, suggesting that they enjoy a highly developed sensitivity to subtle deviations of rhythm. We demonstrate that pre-attentive brain responses recorded with magnetoencephalography to rhythmic incongruence are left-lateralized in expert jazz musicians and right-lateralized in musically inept non-musicians. The left-lateralization of the pre-attentive responses suggests functional adaptation of the brain to a task of communication, which is much like that of language.

Acoustic Stimulation↗
PubMed2005

Concrete spatial language: see what I mean?

Conveying complex mental scenarios is at the heart of human language. Advances in cognitive linguistics suggest this is mediated by an ability to activate cognitive systems involved in non-linguistic processing of spatial information. In this fMRI-study, we compare sentences with a concrete spatial meaning to sentences with an abstract meaning. Using this contrast, we demonstrate that sentence meaning involving motion in a concrete topographical context, whether linked to animate or inanimate subjects nouns, yield more activation in a bilateral posterior network, including fusiform/parahippocampal, and retrosplenial regions, and the temporal-occipital-parietal junction. These areas have previously been shown to be involved in mental navigation and spatial memory tasks. Sentences with an abstract setting activate an extended largely left-lateralised network in the anterior temporal, and inferior and superior prefrontal cortices, previously found activated by comprehension of complex semantics such as narratives. These findings support a model of language, where the understanding of spatial semantic content emerges from the recruitment of brain regions involved in non-linguistic spatial processing.

Acoustic Stimulation↗
PubMed2004

What's at the top in the top-down control of action? Script-sharing and 'top-top' control of action in cognitive experiments.

The distinction between bottom-up and top-down control of action has been central in cognitive psychology, and, subsequently, in functional neuroimaging. While the model has proven successful in describing central mechanisms in cognitive experiments, it has serious shortcomings in explaining how top-down control is established. In particular, questions as to what is at the top in top-down control lead us to a controlling homunculus located in a mythical brain region with outputs and no inputs. Based on a discussion of recent brain imaging experiments, we argue for the need to factor the interaction between the experimenter and the experimental participant into a realistic understanding of top-down control. We suggest these interactions involve a 'sharing of scripts' for perception and action that may be described as 'top-top processes.' We thereby expand the understanding of the homunculus to include elements of social cognition. This conceptual reconfiguration may grant some sort of asylum for a--not very omnipotent--homunculus.

Animals↗
PubMed2002

Introspection and cognitive brain mapping: from stimulus-response to script-report.

Cognitive science has wholeheartedly embraced functional brain imaging, but introspective data are still eschewed to the extent that it runs against standard practice to engage in the systematic collection of introspective reports. However, in the case of executive processes associated with prefrontal cortex, imaging has made limited progress, whereas introspective methods have considerable unfulfilled potential. We argue for a re-evaluation of the standard 'cognitive mapping' paradigm, emphasizing the use of retrospective reports alongside behavioural and brain imaging techniques. Using all three sources of evidence can compensate for their individual limitations, and so triangulate on higher cognitive processes.

Journal Article↗
PubMed2002

Imaging the intentional stance in a competitive game.

The "intentional stance" is the disposition to treat an entity as a rational agent, possessing particular beliefs, desires, and intentions, in order to interpret and predict it's behavior. The intentional stance is a component of a broader social cognitive function, mentalizing. Here we report a study that investigates the neural substrates of "on-line" mentalizing, using PET, by asking volunteers to second-guess an opponent. In order to identify brain activity specifically associated with adoption of an intentional stance, we used a paradigm that allowed tight control of other cognitive demands. Volunteers played a computerised version of the children's game "stone, paper, scissors." In the mentalizing condition volunteers believed they were playing against the experimenter. In the comparison condition, volunteers believed they were playing against a computer. In fact, during the actual scanning, the "opponent" produced a random sequence in both conditions. The only difference was the attitude, or stance, adopted by the volunteer. Only one region was more active when volunteers adopted the intentional stance. This was in anterior paracingulate cortex (bilaterally). This region has been activated in a number of previous studies involving mentalizing. However, this is the first study suggesting a specific link between activity in this brain region and the adoption of an intentional stance.

Adult↗