Ana Raposo Research . Publications

Research

My research integrates behavioural measures and neuroimaging data to gain a better understanding of the neurocognitive mechanisms underlying memory retrieval and expression of knowledge. How is our knowledge about objects organised in the brain? How are the words’ meanings shaped by the context? Does prior knowledge affect the recollection of past events? Which brain regions mediate retrieval of general knowledge vs. specific past events?

Semantic representation and control

We investigate how people’s knowledge about concepts (e.g., bird) is functionally organised and neurologically implemented. We have explored the specific functions of the anterior temporal lobe and inferior parietal lobe in integrating multiple features into single coherent concepts. Given our vast semantic knowledge, a critical question concerns how we selectively and flexibly retrieve the information needed to carry out the task at hand, avoiding interference of non-relevant information. I am particularly interested in the role of the prefrontal cortex in exerting control over retrieved semantic representations.

Integration of words into context

Our research has provided evidence about how we access, select and integrate the meaning of words into context. In a set of fMRI and EEG studies, using semantic ambiguity, semantic illusions and semantic predictability, we have explored how the sentential context modulates the meaning attributed to upcoming words and how it enhances inference drawing. We are currently testing the hypothesis that establishing inferences while a sentence unfolds is accompanied by monitoring mechanisms mediated by the frontal cortex that enable the detection and correction of erroneous inferences.

Semantic strategies in episodic memory retrieval

Our memories of past events are edited and reconfigured as a result of knowledge, goals and cues. I am interested in understanding the nature of the semantic operations that support episodic memory and which encoding and retrieval processes benefit from semantics. This work has outlined the role of the prefrontal cortex and its interactions with posterior regions in the flexible use of semantic cues and strategies to promote successful episodic retrieval. Using multivariate pattern analysis, we are investigating how the semantic similarity and distinctiveness of past events impact the way people retrieve those events.