Sleep Disorders

Private laboratory device. (Contributed by Dr. Cibele Dal Fabbro.)

Private laboratory device. (Contributed by Dr. Cibele Dal Fabbro.)

The EMG channels show alternate contractions in both tibialis anterior muscles at about 1 to 2 Hz.

Legend: EOG: electrooculogram, Mylo: mylohyoideus muscle, Ext. Carpi.: extensor carpi muscle, Tib. Ant.: tibialis anterior muscle, ECG: electrocardiogram, Abd. Resp.: abdominal respirogram, R.: right, L.: left.

(Used with permission from Elsevier. From: Baldelli L, Provini F. Fragmentary hypnic myoclonus and other isolated motor phenomena of sleep. Sleep Med Clin 2021;16(2):349-61.)

Brief sequence of repeated activation of the right anterior tibialis can be seen during relaxed wakefulness, at a frequency of about 1 Hz.

Legend: EOG: electrooculogram, Mylo: mylohyoideus muscle,Tib. Ant.: tibialis anterior muscle, ECG: electrocardiogram, Abd. Resp.: abdominal respirogram, R.: right, L.: left.

(Used with permission from Elsevier. From: Baldelli L, Provini F. Fragmentary hypnic myoclonus and other isolated motor phenomena of sleep. Sleep Med Clin 2021;16(2):349-61.)

The EMG activity originates in the left paraspinalis muscle and then spreads to the more cranial and rostral axial and limb muscles, without any rostro-caudal order as better visible at high paper speed (right part).

Legend: EOG: electrooculogram, Mylo: mylohyoideus muscle,Orbic.: orbicularis muscle,Mass: masseter muscle, Delt.: deltoideus muscle, Wrist Extens.: wrist extensor muscle, Rect. Abd.: rectus abdominis muscle, Parasp.: paraspinalis muscle, Rectus Fem.: rectus femoralis muscle, Tib. Ant.: tibialis anterior muscle, ECG: electrocardiogram, Resp. Thor-Abd.: thoraco-abdominal respirogram, R.: right, L.: left.

(Used with permission from Elsevier. From: Baldelli L, Provini F. Fragmentary hypnic myoclonus and other isolated motor phenomena of sleep. Sleep Med Clin 2021;16(2):349-61.)

Brief, asymmetrical, asynchronous potentials are visible in the explored muscles, sometimes without any associated visible movement.

Legend: EOG: electrooculogram, Mylo.: mylohyoideus muscle, Ext. Carpi: extensor carpi muscle, Tib. Ant.: tibialis anterior muscle, ECG: electrocardiogram, Abd. Resp.: abdominal respirogram, R.: right, L.: left.

(Used with permission from Elsevier. From: Baldelli L, Provini F. Fragmentary hypnic myoclonus and other isolated motor phenomena of sleep. Sleep Med Clin 2021;16(2):349-61.)

PSG recording shows spontaneous propriospinal myoclonus jerks (a) in brief clusters or (b) isolated during relaxed wakefulness preceding sleep onset. (c) The recording of a propriospinal myoclonus jerk shows a slow rostro-caudal propagation of muscular activity. At high paper speed, it is evident that the onset of the EMG activity is in the recti abdominis muscles with ordered spreading to more rostral and caudal muscles (dotted line).

Legend: EOG: electrooculogram, Mylo: mylohyoideus muscle, Mass: masseter muscle, SCM.: sternocleidomastoid muscle, Delt.: deltoideus muscle, Intercostalis: intercostalis muscle, Rect. Abd.: rectus abdominis muscle, Parasp.: paraspinalis muscle, Rectus Fem.: rectus femoralis muscle, Tib. Ant.: tibialis anterior muscle, ECG: electrocardiogram, Abd. Resp.: abdominal respirogram, R.: right, L.: left

Used with permission from Elsevier. From: Baldelli L, Provini F. Fragmentary hypnic myoclonus and other isolated motor phenomena of sleep. Sleep Med Clin 2021;16(2):349-61.

(Contributed by Dr. Federica Provini.)

Sleep hypnogram of a patient with Parkinson disease. Total sleep time is markedly reduced as well as sleep efficiency; frequent and sometimes prolonged infrahypnic awakenings are present throughout the night. All sleep phases are represented; REM latency is increased. (Contributed by Dr. Federica Provini.)

(Contributed by Dr. Liborio Parrino.)

Suggested algorithm for evaluating children with restless sleep. (Contributed by Dr. Lourdes M DelRosso.)

Polysomnographic finding of large muscle group movement in a child with restless sleep disorder. (A) Beginning of the movement; (B) middle of the movement; (C) end of the movement with repositioning from lateral decubitus to supine. Notice the artifact on both tibialis electromyogram (tib dx and tib sn) and chin signal (milo). The movement artifact is also reflected in the electroencephalogram leads. (Contributed by Dr. Lourdes M DelRosso.)

(A) Summary of findings from fMRI studies in obstructive sleep apnea. During tasks, activation is reduced in the dorsolateral prefrontal cortex, anterior cingulate cortex, middle frontal gyrus, inferior frontal gyrus, cingulate and parietal regions, bilateral parahippocampal regions, right insula, bilateral claustrum, left precentral gyrus, and right precuneus, depending on the cognitive domain involved. Activation is increased in the right anterior prefrontal gyrus, bilateral inferior and middle frontal gyri, cingulate gyrus, junction of the inferior parietal and superior temporal lobes, thalamus, cerebellum, parietal cortex, medial precuneus, hippocampus, and left temporo-occipital area. (B) Summary of findings from PET and SPECT studies in obstructive sleep apnea. During sleep, reduced regional perfusion is present in the left parietal region, bilateral parahippocampal gyri, left lingual gyrus, precuneus, middle and posterior cingulate gyrus, parieto-occipital cortex, and prefrontal cortex. Hyperperfusion is present in the frontal cortex during sleep. (Contributed by Dr. Nathan Cross and Dr. Florence Pomares.)

Summary of findings from PET and SPECT studies in REM sleep behavior disorder. During episodes of REM behavior disorder, perfusion is increased within the supplementary motor cortex. At wakefulness, perfusion is decreased in the frontal and temporoparietal cortical regions, and activity is increased in the pons, putamen, hippocampus, medial parietal areas, and occipital areas and in the cerebellum and limbic system. (Contributed by Dr. Nathan Cross and Dr. Florence Pomares.)

(A) Summary of findings from fMRI studies in narcolepsy. During winning on a gambling task, activity is reduced in the bilateral nucleus accumbens and the ventromedial prefrontal cortex, and activity is increased in the putamen and inferior lateral frontal cortex. During an encoding and recognition task, there is more deactivation within the default mode network. In response to the presentation of humorous images, decreased activation is present in the right hypothalamus, medial prefrontal cingulate cortex, nucleus accumbens, and hypothalamus. Increased activity is present in the right inferior frontal gyri and amygdala. (B) Summary of findings from PET and SPECT studies in narcolepsy. During sleep, activity in temporoparietal regions of the cortex and cerebellum is increased; perfusion within parietal regions is increased during REM sleep. During wakefulness, there is decreased perfusion in the brainstem, cerebellum, caudate nucleus, subcallosal gyrus, and cingulate gyrus extending along the corpus callosum. Glucose metabolism is decreased in the parahippocampal gyrus, bilateral paracentral areas, bilateral hypothalami, thalamic nuclei, and frontal-parietal cortices. Hypermetabolism is present in the anterior and midcingulate cortex, the right cuneus, and the lingual gyrus. (Contributed by Dr. Nathan Cross and Dr. Florence Pomares.)

(A) Summary of findings from fMRI studies in insomnia. Overall, there is an increased activation in response to sleep-related and emotional stimuli in the left temporal (including amygdala) and occipital lobes and right frontal lobe. A decreased activation in response to other types of stimuli, such as tasks involving executive control, occurs in the left medial and inferior frontal gyrus, dorsolateral prefrontal cortex, anterior and posterior cingulate cortex, and orbitofrontal cortex. In addition, at rest, the activation is decreased in the amygdala, insula, striatum, thalamus, medial prefrontal cortex, middle temporal gyrus, and left temporal and left inferior parietal cortex, whereas connectivity between the amygdala and premotor cortex is increased. (B) Summary of findings from PET and SPECT studies in insomnia. During wakefulness, there is an overall decreased perfusion across regions of the frontal, temporal, parietal, and occipital cortices as well as in the thalamus, hypothalamus, and brainstem reticular formation. The overall activity decrease in the default mode network in the transition from wakefulness to sleep is less pronounced in insomnia. During NREM sleep, decreased regional cerebral blood flow is present in the frontal medial and frontal lateral cortex; occipital, temporal, and parietal cortices; thalamus; basal ganglia; and pons. (Contributed by Dr. Nathan Cross and Dr. Florence Pomares.)

A 67-year-old Caucasian male with a history of sleep-related laryngospasm, excessive daytime sleepiness, and MSA. The video-polysomnography showed persistent laryngospasm, REM sleep behavior disorder, and severe obstructive sleep apnea syndrome. In this video, the patient is in REM sleep; sleep-related laryngospasm is not associated with oxygen desaturation and patient is not awakened by it. (Contributed by Dr. Michela Figorilli.)