Interview With Dr Mahncke: The Impact Of Traumatic Loss On Brain Health

By Alice Duthie
on 17 August 2023

Most of us have experienced loss and grief in some form, but what you might not be aware of are the physical, chemical, and functional effects this has on the brain.

Dr Henry Mahncke is a neuroscientist and CEO of Posit Science, the organisation that created the BrainHQ app. His app works to monitor the moods and mental states of soldiers who have experienced loss, grief, and high-stress situations. The app has also been designed to help military personnel recover from traumatic brain injuries.

Here, we spoke with Dr Mahncke to find out more.

loss Dr Mahncke
Dr Mahncke

Could you share how loss and grief can have an impact on cognitive function?

Grief is a normal reaction to loss. It engages the brain’s fight or flight mechanism, as does any threat to survival. How you work through your grief can impact your behaviour, your bodily function, (such as blood pressure and hormones), and your brain function. Traumatic loss heavily engages brain plasticity – your brain rewires itself, making new neural connections that associate the loss with the life events and experiences that accompany the loss. Low to moderate stress associated with grief for a period of time can be helpful, as the brain works through your adjustment to loss. However, chronic stress for a long period time isn’t good for the brain (or the body) – and it can impair cognitive function. It’s important to experience and work through your loss, often with the help of friends and family, and then come out the other side – changed, but not harmed, by the experience of loss.

In what ways can monitoring moods and mental states help military personnel navigate challenging times?

Members of the military are often in demanding and stressful situations. We’ve done some interesting research in this area with the military in which personnel were asked to record their mental state several times a day on a custom app, by clicking on the “smiley face” symbol that best reflected their current mental state. This was found to provide military mental health experts with more accurate and actionable information than more traditional methods that asked troops to reflect on their feelings over the past several weeks. The goal of the research was to find simple applications that could help with timely interventions and that could reduce churn in the military, leading to longer and happier careers.

Could you tell us about the reason the BrainHQ app was created, and how it is helping military personnel?

BrainHQ came out of research into brain plasticity – the ability of the brain to change (chemically, physically, and functionally) at any age or condition, based on learning and life experiences – conducted at UCSF and other universities around the globe.

Our first target was to help older adults with cognitive aging. Cognitive performance (such as attention, speed of processing, memory, and reasoning) tends to peak in your late 20s, and then diminishes by very small amounts in subsequent years. The changes are so small they tend not to be very noticeable until middle age, when people start to notice occasional memory lapses, or issues with word-finding. When I was in grad school decades ago, scientists knew that the brains of all animals were plastic and could be trained to improve at any age. In fact, my academic mentor when I got my PhD in neuroscience was Dr. Michael Merzenich, who won the Kavli Prize in neuroscience for ground-breaking work showing that the brain is plastic throughout life. One day, he called me to say we had helped a lot of rats and monkeys build better brains and it was about time to help humans do that!

I joined him at Posit Science, where we and the team developed the first versions of the BrainHQ computerized brain exercises. We started with a focus on people in their 80s. When we found we could help them, we turned to people in their 60s and 70s. We also expanded the research with promising results in pre-dementia.

Then, we and our collaborators started paying attention to the observation that the cognitive profile of a person with “brain fog” – whether it was from chemobrain, or HIV-associated neurocognitive disorder, or multiple sclerosis, or heart failure, or a more serious condition like schizophrenia or bipolar disorder – looked a lot like the cognitive profile of an older person with ordinary age-related cognitive decline. As a result, a lot of studies put BrainHQ to work in these populations – and found benefits to brain health and cognitive performance.

Those results led to the question of if BrainHQ could help soldiers and Veterans with cognitive symptoms after so-called “mild” traumatic brain injuries (or TBIs, the signature injury of the recent wars) from concussions and blast exposures. The BRAVE trial, published in 2021, showed BrainHQ was the first highly-scalable technology to successfully address persistent cognitive injuries after mild TBIs. Later studies showed a similar impact in moderate and severe TBIs. There are now more than 200 peer-reviewed published studies of BrainHQ across varied populations.

In early August, the U.S. National Institutes of Health announced that BrainHQ was one of a handful of interventions selected for clinical trials to address long Covid, so the research on new areas that might benefit from BrainHQ is still expanding.


What evidence has shown that the app is effective for soldiers? What did the testing process look like?

BrainHQ makes the brain faster and more accurate in processing sensory information. Those are the building blocks for why it also improves higher brain function, such as memory and decision-making. A number of elite athletes and sports teams began using BrainHQ because it helps with split-second observations and decision-making. While we had been working with the military for a while on brain injuries, we began to do work with them on readiness and resilience. That has included work with Special Operations Command in taking operators who are already kind of superhuman and making them even more superhuman.

We’ve participated in a number of studies and done a lot of research with the military, as well as other peak performers outside the military. For example, what’s called “a shoot/don’t shoot study” asked law enforcement officers on a live-fire shooting range to shoot at a target holding a gun and withhold fire from the same target holding a cell phone. Targets popped up for a just split-second all over the range as officers shot or withheld. They were measured before training and then after just 5 hours of training. They showed a 29% improvement in overall accuracy and a 60% improvement in the most common and consequential error (shooting the guy with the cell phone).

Are there any specific cognitive exercises or techniques that have shown significant results in assisting soldiers with cognitive recovery?

The exercises can be targeted to specific goals. For example, if you play sports, visual speed and accuracy is most important so there are core exercises for sports, or if you work in counselling or tele-sales, the exercises focused on auditory processing and social cognition might be most important. BrainHQ has an AI system that looks at your goals and your performance on all prior sessions and recommends what to do next, which is what people recovering from a brain injury tend to use, or you can choose what we call a Focus, which is a course that focuses on particular cognitive goals, like being better at sports or at listening.

What does the future look like for BrainHQ?

Our focus is on building the best and most scientifically-validated brain exercises and assessments in the world. We continue to be surprised by new applications for a system that delivers a faster and more accurate brain, whether its research in new clinical conditions that affect brain health, or deployment with no co-pay in leading Medicare Advantage plans, or in new occupations and situations where cognitive performance can provide a crucial edge. Based on the results to date, I can say BrainHQ is for everyone – from grandmas to astronauts, stroke patients to pro football players, from TBI patients to special forces.

Dr. Mahncke got his PhD in Neuroscience at the University of California, San Francisco in the Merzenich Lab, which discovered the brain remains “plastic” – capable of chemical, structural and functional change – at any age. Then, at the request of his academic mentor, Dr. Mahncke led a global team in harnessing that plasticity through the computerized brain exercises found in the BrainHQ app, which is produced by Posit Science, where he is the CEO. BrainHQ can be found at

Related News

More WLT News