MENTAL IMAGERY | Prof. Emily A. Holmes

What is Mental Imagery?

We think in the form of either words or mental imagery, though know less about the latter. Mental imagery is like weak perception (without the percept) recruiting similar neural circuitry. Imagining daffodils, as Wordsworth wrote, “that flash upon that inwards eye” brings solace. Negative events flashing into mind, like intrusive memories of trauma, bring overwhelming emotions. Allowing time travel, imagery can “flash-forwards” to suicide. By amplifying emotion and behaviour, imagery drives psychopathology across mental disorders. Directly asking patients about mental imagery benefits assessment. Being curious about mental imagery enriches the science of mental life, and may also open doors clinically.

Holmes, E. A. & Ågren, T. (2020). “100 words on mental imagery – 100 words”. The British Journal of Psychiatry, 216(4), 196-196.

When we go through day-to-day life, a lot of our experience gets saved in the brain in the form of memories. Memories help us learn about the world, inform our personality, and they help us learn to handle new situations.

When our brain processes our experience into a memory, the brain connects details of what we experienced to the time when and place where we experienced them. For example, if you go on a beach holiday in England, your brain may create a connection of the sounds of the sea and the sight of beach chairs (sensory details) to last summer (when) and the beach’s location (where).

Memory storage is not limited to a single area in the brain, but rather spread across different brain areas. Sensory details of our memories are stored in the areas of the brain that process the respective senses, whereas the ‘when’ and ‘where’ tags are stored in a separate set of regions in the brain.

When a friend asks you a few weeks later how your vacation was, you try to remember your holiday. Like searching for a film in an archive, your brain pulls the ‘when’ and ‘where’ tags which reactivate the sensory details. This is like projecting the sensory details from the holiday on the screen of your mind’s eye. Even though you are not on the beach in England anymore, you may be able to visualize the scenery of the holiday in your mind’s eye: the colour of the sea, the pattern of the beach chairs. Researchers call this capacity to picture something from our past ‘mental imagery’.

When something very negative and emotional happens to us, like a car accident, it might be that the process of tagging the experience goes wrong. The sensory details of these highly distressing situations are not properly connected to their ‘when’ and ‘where’ tags. Because of this, they can pop back into our minds, even in situations when we are not actively trying to remember them.

These memories are called ‘intrusive memories’ because they appear when we are not deliberately trying to recall them. Instead of selecting the film roll ourselves, details of the car accident may project on the screen in our mind’s eye out of the blue. That is, the image “pops up” involuntarily.

But mental imagery is not only related to past experience. Our capacity to mentally picture things also allow us to manipulate them, like imagining a shape and rotating it in our mind’s eye. This process is also called mental rotation and is something that we use when playing Tetris^® and picturing where the blocks would fall.

So, how can this help with intrusive memories?

Researchers believe that briefly recalling a memory shifts the memory into a state where the connections between the sensory details and the ‘where’ and ‘when’ tags can be changed. For instance, occupying the mind’s eye with a task (such as mental rotation during Tetris^® ) after being reminded of an experience will make it harder for the sensory details to play out. In this way, the intensity of these sensory details can be down-regulated. This makes the unwanted image less likely to intrude to mind.

With many thanks to Dr. Hannah Bernhard.