Biology subjects

Vigano, S.

Publications and source records attributed to Vigano, S..

7 recordsLinked to original sources

bioRxiv2026

The Brain Encodes Pure Logic Beyond Natural Language And At The Boundaries With Mathematics

You are not not reading this sentence. True, because you are. It's the law of double negation, a logical rule that states that a statement that is not not true is itself true. The development of pure logic - the study of the properties of formal systems, irrespective of their content - represents one of the most abstract intellectual achievements of human culture. Yet its neural correlates remain vastly unexplored. Is pure logic represented in a linguistic format like natural language, in an abstract symbolic format like other formal systems such as mathematics, or as a fully distinct domain of knowledge? To address this question, we monitored the brain activity of professional logicians and matched controls while they evaluated the truth of spoken statements of pure logic, and compared these activations to those elicited by language and mental arithmetic. We show that pure logic recruits left-lateralized brain circuits that are completely distinct from those involved in language processing. Those circuits only partially overlap with those involved in mathematics. These findings highlight an independent neural pathway for abstract thought and indicate that the brain's capacity to process structured rules of formal systems is implemented beyond language and at the boundaries with mathematics.

neuroscience↗

bioRxiv2026

Ribosome Quality Control Mitigates Proteotoxic Stress in Aneuploid Cells

Aneuploidy is widespread in tumors, but how cancer cells adapt to aneuploidy-induced cellular stresses remains poorly understood. Here, we focus on the mechanisms employed to cope with proteostasis disruption, a major stress caused by aneuploidy. We show that aneuploid cells exhibit a significant accumulation of ribosomes enclosed within autophagosomes, ultimately degraded through lysosome-mediated processes. Our data also indicate that limited folding capacity of newly synthesized polypeptides leads to lysosome-mediated degradation of ribosomes. We also found that the E3 ligase ZNF598 marks these ribosomes for degradation, thus clearing translationally-impaired ribosomes. Importantly, highly aneuploid tumors display a positive correlation with ZNF598 expression, while being negatively associated with ribosomal signatures. This suggests that ribosome-associated quality control is crucial for cancer cell survival under proteotoxic stress. Our study uncovers molecular events in response to proteotoxic stress in aneuploid cells and suggests that components of ribosome-associated quality control, including ZNF598, could serve as promising targets in cancer therapy.

cell biology↗

bioRxiv2025

Foraging in conceptual spaces: hippocampal oscillatory dynamics underlying searching for concepts in memory

How does the brain access stored knowledge? It has been proposed that conceptual search engages neurocognitive processes similar to foraging in physical space. We tested this idea using intracranial EEG in patients performing a verbal fluency task, where they spontaneously explored their own knowledge of the world, sampling words from semantic memory. We found that hippocampal theta power increased during conceptual search and scaled with the semantic distance between successive words, paralleling dynamics observed in spatial navigation. Critically, people transitioned between conceptual clusters, resembling transitions between resource patches in foraging behavior. These shifts were marked by enhanced theta-gamma coupling, both within the hippocampus and between the hippocampus and lateral temporal cortex, a key hub of the semantic network. These findings support a mechanistic account of memory search grounded in navigation and foraging principles, suggesting that the hippocampus orchestrates local computations and long-range interactions to enable flexible retrieval of conceptual knowledge.

neuroscience↗

bioRxiv2024

Hippocampal-entorhinal cognitive maps and cortical motor system represent action plans and their outcomes

Efficiently interacting with the environment requires weighing and selecting among multiple alternative actions based on their associated outcomes. However, the neural mechanisms underlying these processes are still debated. We showed that forming relations between arbitrary action-outcome associations involved building a cognitive map. Using a novel immersive virtual reality paradigm, participants learned 2D abstract motor action-outcome associations and later compared action combinations while their brain activity was monitored with fMRI. We observed a hexadirectional modulation of the activity in entorhinal cortex while participants compared different action plans. Furthermore, hippocampal activity scaled with the 2D similarity between outcomes of these action plans. Conversely, the supplementary motor area (SMA) represented individual actions, showing a stronger response to overlapping action plans. Crucially, the connectivity between hippocampus and SMA was modulated by the similarity between the action plans, suggesting their complementary roles in action evaluation. These findings provide evidence for the role of cognitive maps in action selection, challenging classical models of memory taxonomy and its neural bases.

neuroscience↗

bioRxiv2023

Mental search of concepts is supported by egocentric vector representations and restructured grid maps

The human hippocampal-entorhinal system is known to represent both spatial locations and abstract concepts in memory in the form of allocentric cognitive maps. Using fMRI, we show that the human parietal cortex evokes complementary egocentric-like vector representations in conceptual spaces during goal-directed mental search, akin to those observable during physical navigation to determine where a goal is located relative to oneself. Concurrently, grid-like representations, a neural signature of allocentric cognitive maps in entorhinal, prefrontal, and parietal cortices, are restructured as a function of conceptual goal proximity, akin to rodent grid cells firing around reward locations during spatial exploration. These brain mechanisms might support flexible and parallel readout of where target conceptual information is stored in memory, capitalizing on complementary reference frames.

neuroscience↗

bioRxiv2020

Multiple spatial codes for navigating 2-D semantic spaces

When mammals navigate in the physical environment, specific neurons such as grid-cells, head-direction cells, and place-cells activate to represent the navigable surface, the faced direction of movement, and the specific location the animal is visiting. Here we test the hypothesis that these codes are also activated when humans navigate abstract language-based representational spaces. Human participants learnt the meaning of novel words as arbitrary signs referring to specific artificial audiovisual objects varying in size and sound. Next, they were presented with sequences of words and asked to process them semantically while we recorded the activity of their brain using fMRI. Processing words in sequence was conceivable as movements in the semantic space, thus enabling us to systematically search for the different types of neuronal coding schemes known to represent space during navigation. By applying a combination of representational similarity and fMRI-adaptation analyses, we found evidence of i) a grid-like code in the right postero-medial entorhinal cortex, representing the general bidimensional layout of the novel semantic space; ii) a head-direction-like code in parietal cortex and striatum, representing the faced direction of movements between concepts; and iii) a place-like code in medial prefrontal, orbitofrontal, and mid cingulate cortices, representing the Euclidean distance between concepts. We also found evidence that the brain represents 1-dimensional distances between word meanings along individual sensory dimensions: implied size was encoded in secondary visual areas, and implied sound in Heschls gyrus/Insula. These results reveal that mentally navigating between 2D word meanings is supported by a network of brain regions hosting a variety of spatial codes, partially overlapping with those recruited for navigation in physical space.

neuroscience↗

bioRxiv2017

How emotional memory affects face remembering: an ERP investigation

It is known that the longer an information has been memorized, the stronger is its memory trace. At the same time it is known that the emotionally-valenced information has a stronger memory trace than neutral one. Interactive effects between these factors are largely unknown. In this study electrical neuroimaging signals were recorded in healthy controls to explore the neural mechanism of memory for faces of different emotional valence, sex, learning context and temporal recency. In a study phase participants familiarized with the fictional police dossier of 10 victims of dramatic deaths including homicide or earthquake (depicted as attractive and nice persons of about 45 years), twice a day for seven days before EEG recordings. Hundreds of famous movie stars (overlearned), victims (recent) and new faces were presented in an old/new recognition task. ERP responses showed a modulation of anterior N2 and FN400 as a function of face familiarity (with no differences between overlearned and recent faces), while parietal late positivity was sensitive to engram temporal recency (it was much larger to overlearned than recent faces, paralleling behavioral data). However, LP amplitude did not differ to overlearned vs. recent same-sex faces, showing how emotional memory can enhance faces remembering. A late frontal negativity revealed sensitive to source memory.

neuroscience↗