File:Circuits-for-imaginations.png

English: The diagram of the circuits responsible for perceptions and recalling of mental images. The essential elements of the scheme are three layers of the hierarchical structure of neurons integrating sensory information, for instance – in the visual pathways. The traces of long term memory are consolidated under the influence of connections from hypothalamus and amygdale (A). The cortico-hippocampal loops (B) are elements of the working memory system recalling mental images. The activation of the object neuron by the cortico-hippocampal loop induces recurrent reactivation of neurons in lower layers. The dotted line indicates the circuits of repetitive propagation of stimuli in the upper layers of the hierarchical structure, which is the essence of imaginary. The activation of an object neuron can also be evoked from the side of the speech area (C). The thalamo-cortical loop (D) reach the lower parts of the cortex. The oscillations in these circuits happens e.g., in periods of a deep sleep. The element “D” of the diagram emphasize that the brain’s actions are based on an intrinsically generated neuronal activity and that the sensory inputs are acting as modifiers of such intrinsic activity. Mental imagery is the essence of episodic memory, short term memory and is used for working memory activity. The diagram also shows that during the implementation of imagination not only a certain process takes place, but also a certain object is produced, existing in time and space, the essence of which consists in the temporary existence of a certain electromagnetic shape.