Updated: Aug 13
Negative thoughts seem to be bad for your brain in addition to hijacking your joy. Anyone who has ever had to deal with low mood or a mild depressive experience knows how easy it is to fall into the trap of a constant negative thought feedback loop. Negative thinking can become a habit and detrimental to not only your mental health but physical health as well. Your thoughts are simply chemical and electrical patterns in your brain.
It turns out that repetitive negative thinking can even put you at risk for dementia, according to a new study published in the journal Alzheimer’s & Dementia. Specifically, the phenomenon known as repetitive negative thinking (RNT) was demonstrated to be a potential risk factor for early Alzheimer’s disease symptomatology.
The power of your thoughts is often underestimated; you hear about how thinking positively can often turn a bad situation around. If the same is true for negative thoughts, we need to understand exactly why our thinking patterns hold such cognitive power and can affect our physiology.
Mind-wandering is known to influence other aspects of cognition
Does this sound familiar to any of you: you’re going through a rough patch, and you confide your worries in a friend. They listen, attend, and at the end of your story they turn to you and say, “try to think positively.”
Annoying? Yes. Scientifically accurate? Surprisingly, also yes.
Psychologists and cognitive neuroscientists have known for years the impact of our thoughts and the general content of our minds. Cognitive reappraisal is a known technique of applying positive emotional perspectives onto negative events, and it has been shown to be effective for mitigating unpleasant emotional states. By re-accessing and reinterpreting past negative experiences in a more positive language and perspective, reappraisal is an effective way of improving mood. This means that while, yes, the advice your friend gave you is cliche, it’s also a scientifically sound method for helping you overcome your obstacles. Although this might be a scientifically sound technique, it’s equally important to not deny negative feelings or experiences.
Beyond directed cognitive reappraisal, general mind-wandering itself exerts influence over our everyday lives, even if we are not fully aware of it. Mind-wandering affects our mood, problem-solving ability, and our attention. It appears that even when our brains are not engaging in a particular activity, cognitively significant processes are still at play. While mind-wandering is known to interfere with retention, recent evidence suggests that as a brain state, engaging in it increases our capacity to perform more complex operations, effectively.
Negative thought patterns are associated with increased risk of dementia
Negative thought patterns are typically found in other psychological ailments such as mood disorders like depression or anxiety. They are often a part of the overall symptoms of the diagnosis and are sometimes considered a contributing risk factor to depression. Negative thinking can contribute to the development of depression and then perpetuate it. This can become a vicious cycle that has neurobiological consequences.
However, recent clinical evidence suggests negative thought patterns not only have a strong association with mood disorders but may also be associated with age-related cognitive decline. A team from University College London recently published that repetitive negative thought content correlated significantly with known early biomarkers for Alzheimer’s disease in patients who didn’t yet have dementia. In their study they showed:
Increased amyloid load in the brain
Increased entorhinal tau
Declines in global cognition and working memory
These associations between negative thought patterns and preclinical AD pathology suggests that repetitive negative thinking (RNT) may itself be symptomatic of early dysfunction in individuals at risk for dementia. Subjects with cognitive impairment, for example, have been shown to exhibit high cortisol levels coupled with low brain activity, but surprisingly, individuals with negative emotions display high cortisol but high brain activity. This suggests an interference of negative thought content on cognitive functioning, a possible bridge between the pathology and the symptomology of early cognitive decline, and repetitive negative thinking.
Can these negative patterns be halted through positive mind wandering?
Negative mind wandering is a clear detriment to not only our psychological well-being but the state of our brain health in general. This begs the question; if negative thought content and repetitive negative thinking can Be neurologically detrimental, can positive thinking and reappraisal be protective?
In adolescents, positive thinking has been shown to mitigate depressive and anxiety states in the short and medium-term. In adults, positive mental imagery assisted in propagating greater behavioral activation in patients. Meditation has also been found to reduce default mode network activation that extends beyond task-directed attention, which suggests that DMN in mind wandering is related to wellness techniques. These cases suggest that positive mental restructuring has pathology-improving capabilities, but the exact mechanism underlying this relationship requires further study.
Psychological and pharmacological interventions when combined can effectively treat people with depression and this combined treatment can effectively increase the size of the hippocampus, an area that is often diminished in size and people who have chronic depression.
As we go through life, our minds require just as much attention as our physical bodies do; we need to start thinking of our brains as capable of flexibility and growth; to be maintained and rewarded with a good diet, growth mindset, and consistent sensory stimulation. If we can better understand our minds through self-awareness and meditation practices we May be able to change our thinking patterns. Since negative thoughts may be a major factor in dementia risk, it is up to us to practice everyday mindfulness, and keep our brains healthy and, quite literally, happy.
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