Traumatic Brain Injury and Ageing

Written by Sofia Amirbayat
Edited by Rowena Fletcher-Wood

The brain is a complex organ that has a natural ability to adapt and change with time; it is made of about 100 billion neurons, able to connect to each other in networks and pathways. What makes these networks is our lived experiences with the world and people. When a baby is born, the brain has specialised areas for sensory perception, but doesn't have many learned pathways yet and is very open to learning and forming networks.

Lateral View of the Brain by BruceBlaus [CC BY 3.0], via Wikimedia Commons.

There are several interesting parts of the brain, but perhaps the most interesting is the prefrontal cortex. The prefrontal cortex is involved in higher cognition, planning, decision making, personality and social behaviours. There is one category of cognition that is often associated with the prefrontal cortex: executive functions – a group of complex mental processes and cognitive abilities such as working memory, impulse inhibition, and reasoning.

Patients with prefrontal cortex damage can experience blunted emotional responses, which may negatively affect their ability to make decisions. This can lead to them failing to see the consequences of their actions (what we call “thinking ahead”).

How does the structure of the brain change as you age?

When is a Strawberry No Longer a Strawberry?

You take that first bite, tearing through the cells of the red berry and allowing its fragrance to erupt. Juices ooze, coating your mouth. The sweetness, modulated with a slight bitter hint, hits your tongue and lights up your senses, and the distinctive flavour of the strawberry overflows.

Why do we love strawberries so much?

Why do we love strawberries so much? There’s something alluring about them, something intense and complex in the flavour we experience that is not matched by any other berry – its chemistry.

When we recognise a flavour – the combined experience of taste, mouth feel and (crucially) smell – we are actually recognising the aromatic chemistry of a food, the volatile molecules given off when we bring it close to our nose or after we bite into it. When we understand the molecules that make up the distinct chemical profile of a flavour, we can replicate it by creating those chemicals in a lab and stirring them together. This helps us make artificial banana flavour, artificial vanilla flavour, and artificial fresh grass smell. But strawberries are awkward. Strawberry flavour is made up of a chemical medley of many, many different molecules (more than 350), variation exists strawberry species to strawberry species, and we just don’t know how important each chemical is.

This is in direct contrast to the raspberry, a humble berry that we recognise as 4-(4-hydroxyphenyl)butan-2-one, or “raspberry ketone”. Whilst cranberries and blackberries also contain this odour, they mix it with other chemicals, whilst in the raspberry it is exclusively responsible for the raspberry profile we instantly know.

Raspberry ketone, the molecule behind the smell we know so well. © Things We Don't Know.