Subjective experience is probably not limited to humans : The evidence from neurobiology and behavior q Bernard

In humans, conscious perception and cognition depends upon the thalamocortical (T-C) complex, which supports perception, explicit cognition, memory, language, planning, and strategic control. When parts of the T-C system are damaged or stimulated, corresponding effects are found on conscious contents and state, as assessed by reliable reports. In contrast, large regions like cerebellum and basal ganglia can be damaged without affecting conscious cognition directly. Functional brain recordings also show robust activity differences in cortex between experimentally matched conscious and unconscious events. This basic anatomy and physiology is highly conserved in mammals and perhaps ancestral reptiles. While language is absent in other species, homologies in perception, memory, and motor cortex suggest that consciousness of one kind or another may be biologically fundamental and phylogenetically ancient. In humans we infer subjective experiences from behavioral and brain evidence. This evidence is quite similar in other mammals and perhaps some non-mammalian species. On the weight of the biological evidence, therefore, subjectivity may be conserved in species with human-like brains and behavior. 2004 Published by Elsevier Inc. 1053-8100/$ see front matter 2004 Published by Elsevier Inc. doi:10.1016/j.concog.2004.11.002 q I am most grateful to Dr. Gerald M. Edelman and his colleagues at The Neurosciences Institute in San Diego for numerous discussions that have helped to strengthen this special issue of Consciousness and Cognition. * Fax: +1 858 626 2099. E-mail address: [email protected]. 8 B.J. Baars / Consciousness and Cognition 14 (2005) 7–21