Young people at risk of addiction have differences in key brain region
March 4, 2019
Science Daily/University of Cambridge
Young adults at risk of developing problems with addiction show key differences in an important region of the brain, according to an international team led by researchers at the University of Cambridge.
The study adds further evidence to support the idea that an individual's biological makeup plays a significant role in whether or not they develop an addictive disorder.
Adolescence and young adulthood is an important time in a person's development. It is during this time that individuals begin to demonstrate behaviours that are associated with addiction and which suggest that they may be at risk.
One of these behaviours is impulsivity. Sometimes, we need to make quick decisions, for example in response to a danger or a threat. At other times, it is better to hesitate and decide only after careful deliberation. Impulsivity refers to where we respond and act prematurely, without considering the consequences of our actions. While most people occasionally act impulsively, people affected by disorders including attention deficit hyperactivity disorder (ADHD), substance and behavioural addictions, and mental health problems such as depression and anxiety, show much greater levels of impulsivity.
In a study published today in the journal Neuropsychopharmacology, a team of researchers at Cambridge's Department of Psychiatry, in collaboration with a group at Aarhus University in Denmark, has shown a strong association between increased behavioural impulsivity in young adults and abnormalities in nerve cells in the putamen, a key brain region involved in addictive disorders.
As part of the study, 99 young adults aged 16 to 26 carried out a computer-based measure of impulsivity. The researchers also scanned the volunteers' brains using a sequence that is sensitive to myelin content. Myelin is a protein-rich sheath that coats the axis of a nerve cell, analogous to the plastic coating that surrounds electrical wiring, and is essential to fast nerve conduction in the brain and body.
The team found that those young adults who displayed higher measures of behavioural impulsivity also had lower levels of myelin in the putamen. This work builds on similar findings in rodent models of impulsivity from scientists at Cambridge and elsewhere.
"People who show heightened impulsivity are more likely to experience a number of mental health issues, including substance and behavioural addictions, eating disorders, and ADHD," says Dr Camilla Nord of the MRC Cognition and Brain Sciences Unit, lead author on the study.
This suggests that impulsivity is an 'endophenotype', say the researchers; in other words, a set of behavioural and brain changes that increases people's general risk for developing a group of psychiatric and neurological disorders.
"We know that most mental health symptoms are not specific to particular disorders," says Dr Nord. "This work provides an important piece of the puzzle in establishing brain signatures that are general across a number of mental health disorders, rather than specific to any single one."
The putamen is a key brain hub in addiction, sending dopamine signals elsewhere in the brain, and helping mediate how impulsively we behave. "The significance of decreased myelination implies there are tiny microstructural changes in this part of the brain affecting its function, and thereby affecting impulsivity," says senior author Dr Valerie Voon, also from Cambridge.
"The degree of myelination alters the speed and efficiency of neuronal communication, meaning that if a population has decreased myelination only in one particular region, as we show, there is something highly local about any changes in neural speed and efficiency," add co-author Dr Seung-Goo Kim.
Although it is not possible to say definitely whether the decreased myelination causes individuals to behave impulsively, the fact that all participants were healthy and had not been diagnosed with addiction or any other psychiatric diagnosis suggests a more causal link than has been demonstrated in previous studies.
In future, the finding may help in predicting an individual's risk of developing a problem with addiction, say the researchers, but they caution that this would require further research and testing.
The research was funded by the Aarhus University Research Foundation, the Danish Ministry for Social Affairs and the Interior and the UK Medical Research Council. The work was also supported by NIHR Cambridge Biomedical Research Centre.
https://www.sciencedaily.com/releases/2019/03/190304105436.htm
PTSD and Addiction Among Veterans: Causes, Comorbidity, and Treatment
April 2, 2019
By: Cassidy Webb
While the United States is fighting a fatal drug epidemic that is at fault for the deaths of far too many young people, veteran substance abuse continues to pose a growing problem in the nation. As military personnel are returning home from deployment, they are suffering from a vast variety of mental and physical health problems as a result of their experiences. With the comorbidity of co-occurring mental illnesses, such as Post-traumatic Stress Disorder (PTSD), and substance abuse being so prevalent, many veterans are suffering in silence from the progressive, chronic disease of addiction.
PTSD and Veterans
Due to the nature of military service and combat, many veterans are frequently exposed to life-threatening events that can lead to the development of PTSD. When stress is brought on by a traumatic experience, the brain enters a fight or flight response causing the alteration of brain chemicals and heart rate. Adrenaline begins to flow and blood pressure rises. While this response is a natural way for people to protect themselves against harm, those who experience this stress persistently after the danger has passed may have PTSD.
Symptoms of PTSD can begin shortly after the traumatic event occurs and could last a lifetime without treatment. These symptoms can include:
Recall of memories from the event or flashbacks
Difficulty coping with and expressing emotions
May avoid situations that remind them of the traumatic event
Jittery composure or unprecedented anger
Difficulty sleeping
Feelings of hopelessness or despair
Although statistics vary depending on the length of time in the military and the severity of the trauma, there is substantial evidence that veterans suffer from high rates of PTSD. In a study on veterans from Iraq and Afghanistan, it suggests that 14% suffer from PTSD and 39% suffer from alcohol abuse. For Vietnam veterans, rates of PTSD have been found to be as high as 31%. Despite the high necessity for treatment, as many as 50% of veterans who have PTSD do not receive the treatment they need.
PTSD can be a terrifying disorder that is difficult to cope with. For this reason, many veterans turn to alcohol or drugs to cope with their emotions.
Co-Occurring Disorders
The symptoms of PTSD are severe and can cause a lot of emotional distress on those who suffer from it. Unfortunately, many find solace by turning to drugs or alcohol to suppress their emotions and manage their symptoms as drugs and alcohol can increase pleasure, decrease anxiety, and distract an individual from their emotions. The comorbidity of PTSD and drug abuse is so severe that studies have found that nearly 52% of men and 28% of women with PTSD also have a substance use disorder.
While drugs and alcohol may allow individuals with PTSD to cope with their emotions in the short term, this often turns into a pattern of abuse that can lead to an addiction. After a substance is abused over an extended period of time, it becomes harder for the brain to regulate healthy amounts of dopamine. When the substances are suddenly removed, a person may experience a shortage of dopamine resulting in withdrawal symptoms. In turn, using substances to cope with the symptoms of PTSD can actually worsen symptoms. An affected person may suffer from insomnia, impaired judgment, and may engage in risky behaviors such as impaired driving or other illegal, dangerous activities.
Dual-Diagnosis Treatment
The cycle of PTSD and drug abuse is a vicious one if left untreated. On the other hand, if a person seeks treatment but only one condition is treated, they are left highly susceptible to relapse. Fortunately, forms of integrated therapy like dual-diagnosis can help treat both mental illness and substance use disorders simultaneously.
In order to get away from the persistent fight or flight mode that is so common with a PTSD diagnosis, it is important that the individual learns to identify and cope with their PTSD triggers by working closely with psychiatric and addiction specialists. Dual diagnosis therapy will generally consist of different treatment modalities, such as group therapy, individual therapy, cognitive behavioral therapy, and trauma-informed care. Individuals will be encouraged to look at their past and get to the root of their problems as well as learn of healthy coping techniques like deep breathing, meditation, and yoga.
Another benefit of dual diagnosis therapy is that clients will be able to get the right medications, like antidepressants and anti-anxiety drugs, to better treat their mental health. This combination of counseling, support, and medical treatment is typically used to help an individual with co-occurring PTSD and addiction reach a place where they are mentally and physically stable.
Treating addiction hand in hand with mental illness increases the likelihood of maintaining sobriety in the long term, and with the proper diagnosis and medications, symptoms of PTSD can be effectively managed.
Cassidy Webb is an avid writer from South Florida. She advocates spreading awareness on the disease of addiction. Her passion in life is to help others by sharing her experience, strength, and hope. cassidy@recoverylocal.org