Recognition of Familiar Faces and Voices in Persistent Vegetative State Studied by fMRI: Implications for the Neural Mechanism of Consciousness

FACUNDO MANES; SIGMAN L; SILVINA CARPINTIERO; GIANNAULA R; TERESA TORRALVA; LILIANA SABE; LISANDRO OLMOS; RAMÓN LEIGUARDA

Villefranche sur Mer

Encuentro; Research Group on Aphasia and Cognitive Disorders 2002 Annual Meeting; 2002

World Federation of Neurology, Research Group on Aphasia and Cognitive Disorders

Objectives: Assessment of cognitive function is difficult in patients in persistent vegetative state (PVS) because consistent motor responses are lacking. Using Positron Emission Tomography (PET) in a woman in PVS, Menon et al. (1998) showed activation of the right fusiform gyrus and extrastriate visual association areas in response to presentation of familiar faces. The paradigm used in this study paired familiar face stimuli with images obtained by repixellating the photographs to remove structures from the images. However, separating faces from geometric non-faces prevents discerning the specificity of the response. To our knowledge, there have been no studies on voice recognition in patients in PVS. The aims of this work were: a) to investigate specificity of cortical activation after presenting familiar versus unfamiliar faces in a 55-year-old woman (C.V.) in PVS, and b) to evaluate a familiar voice reading an emotional text versus an unfamiliar voice reading an unemotional text in a 17-year-old man (P.M.) in PVS. Patients and Methods: Experiment 1: Familiar faces and blurred unrecognisable images of same, followed by familiar faces vs. unfamiliar faces were shown in a block design on a computer screen, to a 55-year-old woman (C.V.) in PVS. Experiment 2: According to his mother, a 17-year-old man (P.M.) in PVS became emotional many times before the accident when she read him Chapter 21 of “The Little Prince”. Therefore, in a block design paradigm, P.M. listened to his mother reading Chapter 21 of “The Little Prince” and an age-matched voice reading unemotional text. Blood Oxygen Level Dependent (BOLD) images were acquired using a T2-weighted gradient echo planar sequence on a General Electric Sigma CVI, 1.5T system with Real-Time Image Processing (RTIP) of multislice and multiphase images during patient stimulation and rest periods. fMRI post-processing was carried out at a Silicon Graphics Octane workstation using Medx 3.4 (Sensor System), including motion correction and Gaussian smoothing filter to produce statistical maps (threshold p