Visual information is processed in parallel via the magno （M） and parvo （P） cellular systems.　The M system comprises the dorsal pathway （V1 to V5/MT） and is important for motion perception and stereopsis.　In contrast, the P system comprises the ventral stream（V1 to V4 of the inferior temporal cortex） and is responsible for fine vision and color/face perception.　Here, we demonstrate that multimodality visual evoked potentials are useful for exploring patients with dementia and autistic spectrum disorder（ASD）.　In mild cognitive impairment（MCI）, the functions of the ventral stream was normal.　Motion perception was normal in horizontal motion （HO） perception, but radial motion（optic flow : OF） processing related to self-motion perception was abnormal.　Similarly, abnormal HO and OF processing was observed in Alzheimer’s disease（AD）, suggesting systemicopathy of the dorsal stream in AD and MCI.　In Asperger’s syndrome （high-functioning ASD）, we found not only impaired threshold face recognition, but also abnormal unconscious face processing for motional faces.　In addition, OF cognition was selectively impaired, indicating impairment of the ventraldorsal system.　In order to explain this complex pathology in a unified manner, a new model of visual network abnormality has been proposed, namely, the concept of functional connectopathy（connectopathy）.

Recent advances in neuroscience, especially in the field of sleep, revealed some of the mechanisms of the ghost tales or ghost like legends.　These are （1） hypnagogic hallucination like （HyH）（Fig. 1）,（2） highway hypnosis or sudden onset REM sleep syndrome like（SRS）,（3） vivid hallucinationlike（VH） and（4） REM sleep behavior disorder（RBD） like and/or non REM sleep parasomnia（NRP） like.　Three of these hallucinations occur in association with sleep, while one（VH） does not necessarily related with sleep.　Until now, it is often mentioned about some of the ‘ghost tales’ or‘tales of specters’ associated with psychological or psychiatric disorders.　We’ve made diagnostic criteria for these hallucinations（Table 1） and classified reliable ghost tales using these criteria（“Nihon Kaidan Shu（Ghosts Tales in Japan）” 142 tales,‘ Toh-No’ Folktales, 41 tales）.　Here we reported that about two thirds of reliable tales could be classified into these four types of hallucinations（Table2）.　According to our analysis, we concluded that HyH is a REM sleep-related hallucination with atonia, and SRS is without atonia （Fig 2）.　We also concluded that some of the tales of monstrous creatures in the night are due to RBD.　These results suggest that some of the reliable ‘ghost tales’ or‘tales of specters’ may be caused by the same pathological mechanisms as sleep disorder or neurodegenerativedisorders.