"Diversity in the Neuronal Machine" provides valuable insights into the topic of interneurons (formally classified by the author as "using GABA as its primary fast neurotransmitter in the normal, non-pathological state") as opposed to the principal excitatory projection neurons of the nervous system. Beginning with the studies and hypotheses of the Nobel laureate Santiago Ramon y Cajal, Dr Soltesz explores the roles of "the so-called neurons with short axons..." as the "elemental components" of cerebral activity.Interneuronal complexity is clearly explained by an in-depth evaluation of several classification schemes that demonstrate the existence of a large variety of interneuronal types. This leads the author to propose a statistical quantification of interneuronal diversity. The question of whether this diversity could explain the evolution of higher intelligence is addressed by the novel applications of network theory to neuronal microcircuit function. Using both mammalian and invertebrate models and computer simulations as examples, Cajal's hypotheses on functional neuroanatomy are extended to incorporate cell-to-cell interneuronal variability as an important factor in the study of interneuronal heterogeneity.In all, this book provides a compelling insight into the relatively unexplored subject of interneurons and their physiological and even evolutionary significance. An added bonus is the inter-disciplinary nature of this book which opens the neuroscientist to novel insights emanating from the fields of computer modeling, network theory and even artificial intelligence. Fascinating reading!!!