Mariana Martins is a PhD candidate at Leiden University and an external member of the SemaSign project team. Her current work focuses on describing the Portuguese Sign Language (LGP) grammar with deaf sign language teachers, and writing an analysis of the emerging sign language of Guinea-Bissau (LGG) with the deaf community of Bissau (thesis topic). She is interested in how the mind shapes language structure in the visual-manual modality, the relationship between gestures and signs, the visual and metaphoric motivations of sign creation, and how signs are organised lexically, morphologically and syntactically in a linguistic system.