abnormal forebrain morphology abnormal brain development abnormal forebrain development MP:0003232 MPheno.ontology abnormal prosencephalon development anomaly in the formation or patterning of the anterior of the three primary divisions of the developing chordate brain or the corresponding part of the adult brain (in vertebrates, includes especially the cerebral hemispheres, the thalamus, and the hypothalamus and especially in higher vertebrates is the main control center for sensory and associative information processing, visceral functions, and voluntary motor functions)