Different Types of Trauma Affect Brain Volume Differently

October 16, 2017 · Posted in Neurobiology · Comment 

brain volume

Post-traumatic stress disorder (PTSD) has been associated with decreased volume of gray matter in the cortex. Research by Linghui Meng and colleagues has revealed that the specific types of trauma that precede PTSD affect gray matter volume differently.

At the 2016 meeting of the Society for Neuroscience, Meng reported that PTSD from accidents, natural disasters, and combat led to different patterns of gray matter loss. PTSD from accidents was associated with gray matter reductions in the bilateral anterior cingulate cortex (ACC) and medial prefrontal cortex (mPFC). PTSD from natural disasters was linked to gray matter reductions in the mPFC and ACC, plus the amygdala and left hippocampus. PTSD from combat reduced gray matter volume in the left striatum, the left insula, and the left middle temporal gyrus.

Meng and colleagues also found that severity of PTSD was linked to the severity of gray matter reductions in the bilateral ACC and the mPFC.

In a 2016 article in the journal Scientific Reports, Meng and colleagues reported that single-incident traumas were associated with gray matter loss in the bilateral mPFC, the ACC, insula, striatum, left hippocampus, and the amygdala, while prolonged or recurrent traumas were linked to gray matter loss in the left insula, striatum, amygdala, and middle temporal gyrus.

Marker of Heart Failure May Predict Brain Deterioration

July 27, 2017 · Posted in Diagnosis · Comment 

heartA protein released into the blood in response to heart failure may be able to predict brain deterioration before clinical symptoms appear. The protein, N-terminal pro-B-type natriuretic peptide (NT-proBNP), is released when cardiac walls are under stress. High levels of NT-proBNP in the blood are a sign of heart disease. A 2016 Dutch study indicated that high levels of NT-proBNP in the blood are also linked to smaller brain volume, particularly small gray matter volume, and to poorer organization of the brain’s white matter. The study by researcher Hazel I. Zonneveld and colleagues, published in the journal Neuroradiology, assessed heart and brain health in 2,397 middle-aged and elderly people with no diagnosed heart or cognitive problems.

Researchers are working to clarify the relationship between cardiac dysfunction and preliminary brain disease, but researcher Meike Vernooij says it is likely cardiac dysfunction comes first and leads to brain damage. Measuring biomarkers such as NT-proBNP may help identify brain diseases such as stroke and dementia earlier and allow for earlier treatment and lifestyle changes that can slow or reverse the course of disease.

Bipolar Disorder and Diabetes Linked

July 19, 2017 · Posted in Risk Factors · Comment 

diabetes linked to bipolar disorderA systematic literature review in 2016 showed a definitive link between bipolar disorder and diabetes. Bipolar disorder almost doubles the risk of diabetes while diabetes more than triples the risk of bipolar disorder. The article by Ellen F. Charles and colleagues was published in the International Journal of Bipolar Disorders.

The review included seven large cohort studies. The studies, based on elderly populations only, examined bipolar disorder and diabetes rates. Charles and colleagues suggested that shared mechanisms could cause both illnesses. New disease models that explain the link between bipolar disorder and diabetes could lead to better treatments.

The review also reported that both bipolar disorder and diabetes were independently associated with risk of cognitive decline and dementia in these elderly individuals. People with diabetes had more brain atrophy on average than others who share their age and gender but did not have diabetes. People with bipolar disorder who also had diabetes and either insulin resistance or glucose intolerance had neurochemical changes in the prefrontal cortex that indicated poor neuronal health. In some cases, these patients also had reduced brain volume in the hippocampus and cortex.

Kynurenine Pathway Suggests How Inflammation is Linked to Schizophrenia

December 20, 2016 · Posted in Neurochemistry · Comment 

schizophrenia

The kynurenine pathway describes the steps that turn the amino acid tryptophan (the ingredient in turkey that might make you sleepy) into nicotinamide adenine dinucleotide. This pathway might be a connection between the immune system and neurotransmitters involved in schizophrenia.

A recent autopsy study by researcher Thomas Weickert and colleagues explored this link by determining that in the brains of people with schizophrenia and high levels of inflammation, messenger RNA for Kynurenine Aminotransferase II (KATII, a step on the kynurenine pathway) was elevated in the dorsolateral prefrontal cortex compared to the brains of people who died healthy and those with schizophrenia but low levels of inflammation.

The KATII mRNA levels also correlated with mRNA levels of inflammatory markers such as glial fibrillary acidic protein and interleukin-6.

Blood measures related to the kynurenine pathway also differentiated people with schizophrenia from healthy controls. People with schizophrenia had lower levels of tryptophan, kynurenine, and kynurenic acid in their blood. The low levels of kynurenic acid in the blood were correlated with deficits in working memory and smaller volume of the dorsolateral prefrontal cortex.

Weickert and colleagues suggest that blood levels of kynurenic acid might provide a measurable indicator of the degree to which people with schizophrenia are experiencing problems with executive functioning (planning and decision-making) and loss of brain volume.

Brain Volumes Affected by Type and Timing of Childhood Abuse

December 13, 2016 · Posted in Risk Factors · Comment 

age when abused affects brain volume

Maltreatment during childhood has been linked to brain changes and mental illness. In a study by researcher Carl M. Anderson and colleagues that was presented at the 2016 meeting of the Society of Biological Psychiatry, maltreatment at particular ages was statistically linked to deficits in the size of certain brain areas in young adulthood.

The brain areas under examination are critical for the regulation of emotion and behavior, and this research suggests that early experiences can stunt their development, perhaps through  altered production of synapses or via the synaptic pruning process that occurs during preadolescence. The details, summarized below, are perhaps less important than the overall finding that maltreatment in childhood affects brain volume, and this effect varies based on the timing and type of maltreatment. Abuse and neglect earlier in life affected the left side of the brain, while later maltreatment affected the right side.

Severity of physical abuse at age 3 affected the volume of the ventromedial prefrontal cortex in women. Physical abuse at ages 3 and 8 in men affected left ventromedial prefrontal cortical volume, while later abuse at ages 7 and 12 predicted volume of the right side.

In women, dorsal anterior cingulate area on the left was predicted by physical abuse at age 5 and by emotional neglect at ages 7 and 11. Later emotional neglect at ages 15 and 16 and physical abuse by a peer at age 10 was associated with smaller right dorsal anterior cingulate. In men, smaller left dorsal anterior cingulate area was predicted by physical neglect at age 2 and emotional abuse by a peer and witnessing abuse of a sibling at ages 5 and 10, and right area by physical neglect at age 12.

Lithium Increases Cortical Thickness in People with Bipolar Disorder

November 28, 2016 · Posted in Current Treatments · Comment 

superior frontal gyrusRecent studies have indicated that bipolar disorder is associated with changes to brain volume, including thinning of the cortex. In research presented at the 2016 meeting of the Society of Biological Psychiatry, researcher Noha Abdel Gawad reported that four weeks of lithium treatment increased cortical thickness in the left superior frontal gyrus. This is the third replication of this finding.

Other research has established that lithium treatment also increases the volume of the hippocampus in people with bipolar disorder. Together the findings provide strong evidence that lithium treatment protects neurons and can reverse brain changes associated with bipolar disorder.

Bad Habits May Reduce Brain Volumes, May Cause Dementia

September 26, 2016 · Posted in Risk Factors · Comment 

bad habits can reduce brain volumes

Smoking, alcohol use, obesity, and diabetes aren’t just harmful to the body. They may actually lead to dementia.

Behavioral risk factors for cardiovascular disease like those listed above have been linked to reduced volume in the brain as a whole and several brain regions,  including the hippocampus, precuneous, and posterior cingulate cortex. A 2015 study by researcher Kevin King and colleagues found that these reduced brain volumes are early indicators of cognitive decline.

King and colleagues analyzed data on 1,629 participants in the long-term Dallas Heart Study. Their cardiovascular risk factors were assessed when they began the study, and their brain volume and cognitive function were measured seven years later.

Alcohol use and diabetes were associated with lower total brain volumes, while smoking and obesity were linked to low volumes in the posterior cingulate cortex.

Low hippocampal volume was linked to past alcohol use and smoking, while lower precuneous volume was linked to alcohol use, obesity, and blood glucose levels.King and colleagues suggested that subtle differences in brain volumes  in midlife are the first sign of developing dementia in participants who were still younger than 50 years of age.

Music, Mindfulness and Exercise Improve Brain Functioning

March 4, 2016 · Posted in Potential Treatments · Comment 

boy playing violin

Psychiatrists should take the lead in endorsing general wellness and encouraging healthy behaviors, says researcher James Hudziak. He suggests that opportunities to practice music, mindfulness, and exercise should be made available to all school children to increase brain health, and that more intensive efforts are necessary for children in families that are at risk for mood and behavioral difficulties or in children who show some dysfunction in these areas. Hudziak has implemented a statewide program in Vermont that encourages families to engage in these healthy practices.

Hudziak and colleagues analyzed brain scans of 232 children ages 6 to 18, looking for relationships between cortical thickness and musical training. They found that practicing an instrument such as the piano or violin increased working memory, gray matter volume in the brain, and the ability to screen out irrelevant noise. Practicing mindfulness increased white matter volume and reduced anxiety and depression. Exercise also increased brain volume and neuropsychological abilities.

Now Hudziak urges parents to advocate for the teaching of music, mindfulness, and exercise in schools as a way of improving general health, especially since music and gym are often the first programs to be cut when schools face budget shortages. Hudziak suggests that opportunities for athletics should be provided to all children, independent of their skill level, rather than only for the best athletes who “make the team.” Intramural teams should be open to all children, including those with less ability or minimal athletic skills. Exercise, teamwork, and friendships benefit all children.

For more information about the programs Hudziak implemented in Vermont, use the internet to search for the Vermont Family Based Approach, see his book Developmental Psychopathology and Wellness: Genetic and Environmental Influences, or call the University of Vermont Medical Center at (802)847-0000 or (800)358-1144.

Another tool that may be useful to parents of children aged 2 to 12 who are at risk for mood disorders is our Child Network, a secure online portal where parents can complete quick weekly ratings of their child’s mood and behavior, which is then graphed over time and can be used to show the child’s doctors how his or her symptoms are fluctuating and how well any treatment is working.

Schizophrenia: The Importance of Catching It Early

January 18, 2016 · Posted in Current Treatments, Diagnosis · Comment 

schizophrenia

By the time psychosis appears in someone with schizophrenia, biological changes associated with the illness may have already been present for years. A 2015 article by R.S. Kahn and I.E. Sommer in the journal Molecular Psychiatry describes some of these abnormalities and how treatments might better target them.

One such change is in brain volume. At the time of diagnosis, schizophrenia patients have a lower intracranial volume on average than healthy people. Brain growth stops around age 13, suggesting that reduced brain growth in people with schizophrenia occurs before that age.

At diagnosis, patients with schizophrenia show decrements in both white and grey matter in the brain. Grey matter volume tends to decrease further in these patients over time, while white matter volume remains stable or can even increase.

Overproduction of dopamine in the striatum is another abnormality seen in the brains of schizophrenia patients at the time of diagnosis.

Possibly years before the dopamine abnormalities are observed, underfunctioning of the NMDA receptor and low-grade brain inflammation occur. These may be linked to cognitive impairment and negative symptoms of schizophrenia such as social withdrawal or apathy, suggesting that there is an at-risk period before psychosis appears when these symptoms can be identified and addressed. Psychosocial treatments such as individual, group, or family psychotherapy and omega-3 fatty acid supplementation have both been shown to decrease the rate of conversion from early symptoms to full-blown psychosis.

Using antipsychotic drugs to treat the dopamine abnormalities is generally successful in patients in their first episode of schizophrenia. Use of atypical antipsychotics is associated with less brain volume loss than use of the older typical antipsychotics. Treatments to correct the NMDA receptor abnormalities and brain inflammation, however, are only modestly effective. (Though there are data to support the effectiveness of the antioxidant n-acetylcysteine (NAC) on negative symptoms compared to placebo.) Kahn and Sommer suggest that applying treatments when cognitive and social function begin to be impaired (rather than waiting until psychosis appears) could make them more effective.

The authors also suggest that more postmortem brain analyses, neuroimaging studies, animal studies, and studies of treatments’ effects on brain abnormalities are all needed to clarify the causes of the early brain changes that occur in schizophrenia and identify ways of treating and preventing them.

Obesity Linked to Illness Severity

December 28, 2015 · Posted in Risk Factors · Comment 

obesity linked to illness severity

In a talk at the 2015 meeting of the International Society for Bipolar Disorder, researcher David Bond reported that 75% of patients in a study of first episode mania had unhealthy body mass indices (BMIs). Forty percent were overweight while thirty-five percent were obese. Higher weight was associated with greater illness severity. Bond said that in other studies obesity has been associated with less time well and a greater risk of relapse into depression.

Obese patients also had lower brain volume, worse memory, and a greater risk of developing early onset dementia compared to other patients. Those who were overweight or obese had a 35% higher risk of developing Alzheimer’s disease.

In a different talk at the same meeting, researcher Roger McIntyre reported that among patients with bipolar disorder, those who were obese have greater cognitive problems and more evidence of inflammation than those who were not obese. He has seen indirect antidepressant effects and other health benefits following weight loss from bariatric surgery.

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