Related Experiment Video
Updated: May 29, 2026
10:46
A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
Seasonality, suicidality and melatonin.
B J Havaki-Kontaxaki1, E Papalias, M-E V Kontaxaki
11st Department of Psychiatry, University of Athens, Eginition Hospital, Athens, Greece.
Psychiatrike = Psychiatriki
|September 15, 2011
Summary
Suicidal behavior shows seasonal patterns, peaking in spring. Altered melatonin excretion, influenced by light exposure, may contribute to this seasonality alongside other factors.
Area of Science:
- Neuroscience
- Psychiatry
- Environmental Health
Background:
- Suicidal behavior exhibits seasonal variations, with peaks often observed in late spring and troughs in winter.
- Previous research explored links between suicidal behavior, climatic factors, psychopathology, and social aspects.
- The role of light exposure and alterations in melatonin excretion in seasonal psychiatric disorders has been investigated.
Purpose of the Study:
- To provide an overview of studies investigating the pathophysiology of melatonin in the context of seasonal variation in suicidality.
- To explore potential explanatory models for the underlying mechanisms driving seasonal patterns in suicidal behavior.
Main Methods:
- Review and synthesis of existing scientific literature on seasonality of suicidal behavior.
- Analysis of studies examining neurobiological, climatic, psychopathological, and social factors.
- Evaluation of research on melatonin excretion patterns and their correlation with seasonal psychiatric disorders and suicidality.
Main Results:
- Most studies indicate a seasonal peak in suicidal behavior during late spring and a trough in winter.
- An inverse relationship was observed between melatonin levels and the seasonal peak in suicides.
- Evidence suggests a complex interplay of factors, including sunlight exposure, influencing the aetiopathogenesis of suicidal behavior.
Conclusions:
- Melatonin's role in the pathophysiology of seasonal variation in suicidality warrants further investigation.
- Sunlight exposure, alongside other contributing factors, may play a significant role in the seasonal aetiopathogenesis of suicidal behavior.
- Understanding these seasonal influences is crucial for developing targeted prevention and intervention strategies.
Related Concept Videos
01:19Management of Insomnia
The sleep cycle, an integral part of human health, consists of several stages with distinct characteristics and functions. It begins with a transition from wakefulness to sleep, known as the light sleep phase, followed by the restorative deep sleep phase, essential for physical recovery and growth. The cycle concludes with the Rapid Eye Movement (REM) phase, characterized by high brain activity and vivid dreaming. Insomnia, a prevalent sleep disorder, involves difficulty falling asleep, staying...
01:27Major Hormones and Their Functions
Hormones, the biochemical messengers produced by endocrine glands, are pivotal in regulating bodily functions and maintaining homeostasis. Each hormone's balance is crucial; imbalances can lead to significant physiological disruptions. Major hormones include oxytocin, cortisol, epinephrine, estrogen, testosterone, thyroxine, growth hormone, insulin, and glucagon.
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and lactation.
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and lactation.
02:45Biological Clocks and Seasonal Responses
The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.
01:17Sedatives and Hypnotics Drugs: Miscellaneous Agents
Sedatives and hypnotics encompass a wide range of substances, each with its unique mechanism of action, uses, and potential adverse effects.
Melatonin congeners like ramelteon (Rozerem) and tasimelteon (Hetlioz) selectively bind to melatonin receptors (MT1 and MT2) and thus mimic the actions of melatonin, a hormone that regulates sleep-wake cycles. Tasimelteon is primarily used for non-24-hour sleep-wake disorder, common in blind patients. They are also used to treat conditions like insomnia...
Melatonin congeners like ramelteon (Rozerem) and tasimelteon (Hetlioz) selectively bind to melatonin receptors (MT1 and MT2) and thus mimic the actions of melatonin, a hormone that regulates sleep-wake cycles. Tasimelteon is primarily used for non-24-hour sleep-wake disorder, common in blind patients. They are also used to treat conditions like insomnia...
01:23Antidepressant Drugs: MAOIs and Other Agents
Atypical antidepressants, including bupropion (Wellbutrin), mirtazapine (Remeron), nefazodone (Serzone), trazodone (Desyrel), and vilazodone (Viibryd), offer unique mechanisms of action. Bupropion weakly inhibits dopamine and norepinephrine reuptake, aiding depression treatment and smoking cessation, with a low risk of sexual dysfunction. Mirtazapine enhances serotonin and norepinephrine neurotransmission, leading to sedation, increased appetite, and weight gain. As a result, it helps treat...
01:27Depressive Disorders: Etiology
Depressive disorders result from a complex interplay of biological, psychological, and sociocultural factors, each contributing uniquely to the development and persistence of the condition. Understanding these factors provides critical insight into the multifaceted nature of depression.
Biological Factors in Depression
Biological predispositions significantly influence the risk of developing depressive disorders. Genetic studies highlight the role of variations in the serotonin transporter...
Biological Factors in Depression
Biological predispositions significantly influence the risk of developing depressive disorders. Genetic studies highlight the role of variations in the serotonin transporter...