Asymmetry of the Intertropical Convergence Zone Asymmetry of the Intertropical Convergence Zone There are a number of explanations of the asymmetry of the Intertropical Convergence Zone (ITCZ), known by sailors as The Doldrums. The ITCZ would be expected to overlie the geographic equator according to symmetric solar radiation. However, the ITCZ is mostly perennial in the northern hemisphere and in the eastern Pacific and Atlantic Oceans. It was originally explained by the asymmetrical distribution of continents. However, the distribution of land and ocean is severely asymmetric in the Indian Ocean, yet the ITCZ moves back and forth there between the southern and northern hemispheres. Continents surround
Convergence-divergence zone Convergence-divergence zone The theory of convergence-divergence zones was proposed by Antonio Damasio, in 1989, to explain the neural mechanisms of recollection. It also helps to explain other forms of consciousness: creative imagination, thought, the formation of beliefs and motivations ... It is based on two key assumptions: imagination is a simulation of perception, brain registrations of memories are self-excitatory neural networks (neurons can activate each other). A convergence-divergence zone (CDZ) is a neural network which receives convergent projections from the sites whose activity is to be recorded, and which returns divergent projections to the same sites. When an experiment is