Seasonal affective disorder following brain injury

Right-sided brain lesions predominate among patients with lesional mania: evidence from a systematic review and pooled lesion analysis

Despite claims that lesional mania is associated with right-hemisphere lesions, supporting evidence is scarce, and association with specific brain areas has not been demonstrated. Here, we aimed to test whether focal brain lesions in lesional mania are more often right- than left-sided, and if lesions converge on areas relevant to mood regulation. We thus performed a systematic literature search (PROSPERO registration CRD42016053675) on PubMed and Web-Of-Science, using terms that reflect diagnoses and structures of interest, as well as lesional mechanisms. Two researchers reviewed the articles separately according to PRISMA Guidelines, selecting reports of adult-onset hypomania, mania or mixed state following a focal brain lesion, for pooled-analyses of individual patient data. Eligible lesion images were manually traced onto the corresponding MNI space slices, and lesion topography analyzed using standard brain atlases. Using this approach, data from 211 lesional mania patients was extracted from 114 reports. Among 201 cases with focal lesions, more patients had lesions involving exclusively the right (60.7%) than exclusively the left (11.4%) hemisphere. In further analyses of 56 eligible lesion images, while findings should be considered cautiously given the potential for selection bias of published lesion images, right-sided predominance of lesions was confirmed across multiple brain regions, including the temporal lobe, fusiform gyrus and thalamus. These, and several frontal lobe areas, were also identified as preferential lesion sites in comparisons with control lesions. Such pooled-analyses, based on the most comprehensive dataset of lesional mania available to date, confirm a preferential association with right-hemisphere lesions, while suggesting that several brain areas/circuits, relevant to mood regulation, are most frequently affected.

Treatment with weak electromagnetic fields attenuates carbohydrate craving in a patients with multiple sclerosis

Pharmacological studies have implicated serotonergic (5-HT) neurons in the regulation of food intake and food preference. It has been shown that the urge to consume carbohydrate rich foods is regulated by 5-HT activity and that carbohydrate craving is triggered by 5-HT deficiency in the medical hypothalamus. Ingestion of carbohydrate foods stimulates insulin secretion which accelerates the uptake of tryptophan, the precursor of 5-HT and melatonin, into the brain and pineal gland, respectively. Thus, carbohydrate craving might be considered a form of "self medication" aimed at correcting an underlying dysfunction of cerebral 5-HT and pineal melatonin functions. A 51 year old woman with remitting-progressive MS experienced carbohydrate craving during childhood and adolescence and again in temporal association with the onset of her first neurological symptoms at the age of 45. Carbohydrate craving, which resembled the pattern observed in patients with seasonal affective disorder (SAD), was attenuated by a series of extracranial AC pulsed applications of picotesla (10(-12) Tesla) flux intensity electromagnetic fields (EMFs). It is suggested that AC pulsed EMFs applications activated retinal mechanisms which, through functional interactions with the medial hypothalamus, initiated an increased release of 5-HT and resynchronization of melatonin secretion ultimately leading to a decrease in carbohydrate craving. The occurrence of carbohydrate craving in early life may have increased the patient's vulnerability to viral infection given the importance of 5-HT and melatonin in immunomodulation and the regulation of the integrity of the blood brain barrier. The recurrence of this craving in temporal relation to the onset of neurological symptoms suggests that 5-HT deficiency and impaired pineal melatonin functions are linked to the timing of onset of the clinical symptoms of the disease. The report supports the role of experimental factors in the pathophysiology of MS.

Calcification of the pineal gland: relationship to laterality of the epileptic foci in patients with complex partial seizures

The right and left temporal lobes differ from each other with respect to the rate of intrauterine growth, the timing of maturation, rate of aging, anatomical organization, neurochemistry, metabolic rate, electroencephalographic measures, and function. These functional differences between the temporal lobes underlies the different patterns of psychopathology and endocrine reproductive disturbances noted in patients with temporolimbic epilepsy. The right hemisphere has greater limbic and reticular connections than the left. Since the pineal gland receives direct innervation from the limbic system and the secretion of melatonin is influenced by an input from the reticular system, I propose that lesions in the right temporal lobe have a greater impact on pineal melatonin functions as opposed to those in the left dominant temporal lobe. Consequently, since calcification of the pineal gland is thought to reflect past secretory activity of the gland, I predicted a higher prevalence of pineal calcification (PC) in epileptic patients with right temporal lobe as opposed to those with left temporal lobe foci. To investigate this hypothesis, the prevalence of PC on CT scan was studied in a sample of 70 patients (43 men, 27 women, mean age: 29.2 years, range 9-58; SD = 10.1) with complex partial seizures, of whom 49 (70.0%) had a right temporal lobe focus. PC was present in 51 patients (72.8%) and was unrelated to any of the historical and demographic data surveyed. In the patients with a focus in the right temporal lobe, PC was present in 46 cases (93.8%) as compared to 5 of 21 patients (23.8%) with left temporal lobe foci.(ABSTRACT TRUNCATED AT 250 WORDS)

Cocaine addiction: relationship to seasonal affective disorder

We report a 25 year-old patient with seasonal affective disorder (SAD) and cocaine abuse who experienced cyclical fluctuations in cocaine craving which were concomitant with seasonal alterations in mood. The temporal association of both disorders in this patient suggests that they may share a common underlying pathophysiology. Since disturbances in circadian rhythms and pineal melatonin functions may in part underlie the pathophysiology of SAD and the psychomimetic effects of cocaine are mediated in part through the pineal gland, we propose that dysfunction of circadian rhythms and pineal melatonin functions may partly mediate the association of SAD with cocaine abuse. This hypothesis may have potential clinical and therapeutic implications for a subgroup of cocaine abusers with SAD since light therapy, which is efficacious in the therapy of SAD, may also prove to be beneficial in reducing cocaine addiction. Furthermore, the report illustrates the need for investigations of environmental cues for cocaine abuse with specific attention given to the effects of light on circadian mood changes.