Figure 3.

(a) Anatomical brain changes in narcoleptic patients assessed by VBM. In narcoleptic patients, cortical gray matter loss was found to affect frontal brain regions,³⁷ temporal regions,³⁸ as well as hypothalamus, cerebellum (vermis) and ventral striatum³⁹ (see also⁴⁰). However, hypothalamus damage is not systematically found in VBM studies.³⁶ (b) Functional brain changes in narcolepsy. Narcoleptic patients show reduced baseline activity during wakefulness (¹⁸FDG PET, SPECT) in several regions including the hypothalamus and mediodorsal thalamic nuclei.^45,46 During cataplexy, one SPECT study reported hyperperfusion in several brain regions including limbic area, brainstem and motor regions⁵¹ (but see also⁵²). 1 = hypothalamus, 2 = nucleus accumbens (right), 3 = frontomesial, 4 = prefrontal (right), 5 = inferior temporal, 6 = inferior frontal, 7 = superior frontal, 8 = inferior parietal lobule, 9 = rectal/subcallosal gyrus, 10 = dorsal thalamus, 11 = hypothalamus, 12 = cingulate, 13 = post central/supramarginal, 14 = caudate, 15 = premotor and motor cortex, 16 = cingulate, 17 = thalamus, 18 = brainstem, 19 = insula (right), 20 = amygdala (right).