What is cognition?

Eleven authors with disparate relevant backgrounds give their view on what is meant by the word "cognition".

Dysfunctional Skin-Derived Glucocorticoid Synthesis Is a Pathogenic Mechanism of Psoriasis.

Glucocorticoids (GC) are the primary steroids that regulate inflammation and have been exploited therapeutically in inflammatory skin diseases. Despite the broad-spectrum therapeutic use of GC, the biochemical rationale for locally treating inflammatory skin conditions is poorly understood, as systemic GC production remains largely functional in these patients. GC synthesis has been well characterized in healthy skin, but the pathological consequence has not been examined. Here we show de novo GC synthesis, and GC receptor expression is dysfunctional in both nonlesional and lesional psoriatic skin. Use of GC receptor epidermal knockout mice with adrenalectomy allowed for the distinction between local (keratinocyte) and systemic GC activity. Compensation exhibited by adult GC receptor epidermal knockout mice demonstrated that keratinocyte-derived GC synthesis protected skin from topical phorbol 12-myristate 13-acetate-induced inflammatory assault. Thus, localized de novo GC synthesis in skin is essential for controlling inflammation, and loss of the GC pathway in psoriatic skin represents an additional pathological process in this complex inflammatory skin disease.

The evolution of dance.

Evidence from multiple sources reveals a surprising link between imitation and dance. As in the classical correspondence problem central to imitation research, dance requires mapping across sensory modalities and the integration of visual and auditory inputs with motor outputs. Recent research in comparative psychology supports this association, in that entrainment to a musical beat is almost exclusively observed in animals capable of vocal or motor imitation. Dance has representational properties that rely on the dancers' ability to imitate particular people, animals or events, as well as the audience's ability to recognize these correspondences. Imitation also plays a central role in learning to dance and the acquisition of the long sequences of choreographed movements are dependent on social learning. These and other lines of evidence suggest that dancing may only be possible for humans because its performance exploits existing neural circuitry employed in imitation.

Origins of spatial, temporal and numerical cognition: Insights from comparative psychology.

Contemporary comparative cognition has a large repertoire of animal models and methods, with concurrent theoretical advances that are providing initial answers to crucial questions about human cognition. What cognitive traits are uniquely human? What are the species-typical inherited predispositions of the human mind? What is the human mind capable of without certain types of specific experiences with the surrounding environment? Here, we review recent findings from the domains of space, time and number cognition. These findings are produced using different comparative methodologies relying on different animal species, namely birds and non-human great apes. The study of these species not only reveals the range of cognitive abilities across vertebrates, but also increases our understanding of human cognition in crucial ways.