In this discussion, we will find out the answer to a common question that pops in our mind, ‘What is the storage capacity of the human brain?”. To reach a conclusion, we will look at the units of information, artificial storage devices, neurological pathways of storing memories, and the types of information the brain stores.
What is the storage capacity of the human brain?
At one point, Paul Reber who is a Professor of Psychology answered a similar question by stating that the human brain can store up to 2.5 petabytes of information. However, the more recent estimates point to 1 petabyte.
How do we reach this estimate?
It has been found that one neuron participates in many impulses at the same time by making many simultaneous connections. Scientists estimate that one neuron has an average of one thousand connections at a time. The total number of neurons is estimated to be one billion. Multiplying one billion with a thousand, we get the estimate as a million gigabytes.
Is the calculation correct?
It would be if the only thing all these connections did was store information. But we must remember that the brain has much more complex tasks to do than just storing information.
Given the infinite amount of information a human brain is exposed to in one’s lifetime, the brain must sort everything out. What information needs to be kept while what needs to be discarded? What needs to be remembered for a short period? In addition to this, the brain has to do many executive jobs as well.
It leads us to think that the calculation may not be as simple as it seems. A recent study has thus estimated the capacity as one petabyte after accounting for many factors.
What are the bits, bytes, gigabytes, and petabytes?
These are the memory units.
Just as any other measurement, the amount of memory needs a unit. Bytes have been used in computers to describe the amount of memory stored.
A bit is one binary digit, either 0 or 1. A byte corresponds to 8 bits and usually equates to a data item. Then come the prefixes. As far as the metric system, a kilo is 103, a mega is 106, giga is 109, and so on.
But the units of memory are a bit different, where one kilobyte equals 1024 bytes, one megabyte (MB) is 1024kb, and so on.
It has been found in a recent study that the brain has 26 different ways to quote information in contrast to the binary system. These correspond to the sizes and other features of the synapses.
How much information do the computers store?
Different technologies have been used to store memory in computers. One of the popular modes is magnetic core memory, the present-day RAMs. MIT’s Whirlwind was the first computer to use the technology. The first IBM commercial core unit in 1954 offered 4,096 36-bit words for a rental fee of $6,100 a month. 
Old computers used bulky hard drives to store a few GBs of memory. Today, the best-reviewed computers claim storage of 1 to 2 terabytes, still far less than a human brain.
What goes in all this memory space?
One may wonder what goes to all this space in the human brain. The list is endless. It has faces, maps, memories of incidents, emotions, sensations, music, smells, steps of physical tasks, skills, minor details of the scenes, imaginations, some of the dreams, the stories we heard, the movies we watched, and much more.
Understandably, some memories take up more space than others. A simple scene may need storing information related to places of different objects, the faces in the room, the sceneries, the color of walls and floor, the voices or noise, smell, etc.
Does the brain ever run out of space?
The answer is no.
When our neurons work together, the storage capacity is exponentially increased. It is often stated that our brain can store as much information as in 300 years of continuous television transmission. It is more than our lifespan!
If you want to explore the topic further, refer to the following article: https://neurotray.com/can-your-brain-get-full/.
If the brain is so efficient, then why do we forget things?
All of us have forgotten something at one point or the other. To forget your keys in the apartment or forgetting to send an important email must be very frustrating. A logical question arises here, if the brain has so much space, then why does it mess up.
The answer is, it is the problem of retrieval of memory. The brain has all the data in its library. Different systems operate to fetch the relevant information from the grand library. These systems are prone to error and make us humans.
How does the brain store information?
Moving to the mechanisms, we need to first see how the information is transferred to the brain. The answer is our senses. As we see, smell, touch, or taste something, the neuronal pathways transmit the information to the brain.
The brain has to decide whether to keep the information or discard it. More than 90 percent of the information is rendered useless and discarded. The remainder is stored as memory.
The hippocampus plays a central role in memory formation. It stores the information as short-term memory which is later consolidated into long-term memory. On the other hand, the amygdala is involved in emotional responses related to memories.
When a piece of information has to be stored, synapses are created. A synapse is a connection between a dendrite and an axon of two neurons. Just as the electronic circuits in computers, synapses in the human brain have a particular map that corresponds to the details of the information. The appendages of neurons make a huge network. The configuration of this network dictates the memory.
This map of synapses is flexible and it keeps on changing. Some of the synapses are consolidated so that the short-term memory is converted into long-term memory while the others become weaker and eventually disappear. This explains the phenomenon of plasticity and also explains why our memories keep on changing.
The more you replay a memory in your mind, the more the synapses become stronger. It explains why our teachers stress repetition.
The energy required to drive all these processes
A simple computer consumes a considerable amount of energy to store only a few gigabytes of information. But our brain is the most energy-efficient computer in the world. It operates on 20 watts of power while awake, as much as a dim light bulb.
This is millions of times less than the energy required by a computer if it had to store the same amount of information. It is thought to be due to the efficient transmission of information to the brain as well as the biochemical process which harvests most of the energy generated.
Frequently asked questions
Is there a limit to brain storage?
According to recent studies, the human brain can store up to a petabyte or a million gigabytes of information. This is more than enough to remember whatever you want. Hence, one need not worry about reaching one’s brain limit.
How does the brain have infinite storage capacity?
At first a neuronal circuit stores a particular piece of information. However, over time brain integrates relevant information and makes new patterns by combining old and new ones. Hence, in theory, the brain has unlimited potential to store information. These processes also result in memories being dynamic and gaps being filled with relevant information or imaginations.
How much information can the brain store in one day?
After measuring the amount of data that enters the brain, scientists have estimated that on average, a person processes 74 GB of information in a day. Remember, an average movie takes up 2GB of space.
How many hours can a human brain study?
It depends on the attention span of the human brain. Most of the estimates lie close to 6 hours though you can re-focus again and again.
How many percent did Einstein use his brain?
Like all others, Einstein used 100% of his brain. Some sources though claim that humans use only 10% of their brains, as shown in the Hollywood movie “Lucy”.
Does your brain store every memory?
No. Your brain sorts out the information according to its relevance and importance. Some of the information is needed only for a short period as far as the person is working on a task; it is called the working memory. Other stays in short-term memory while a small amount of the total information ends up in long-term memory.
It is interesting to note that the memories loaded with emotions have more chance of ending up as long-term memories.
What if we use 100% of our brain?
If all the neurons in our brain began firing together, it will simulate an epileptic seizure. This is what happens in generalized seizures, all the regions of the brain start firing at the same time.
How much learning can the brain take?
As explained before, our brain knows no bounds. So learn as much as you want.
How much information can your subconscious or conscious mind process?
The conscious mind can process only a fraction of information processed by our subconscious mind or the brain as a whole. It means that only a fraction of information is resting on the top shelf while the remaining stays deep in the containers.
Sources state that the conscious mind processes 40 to 50 bits of info/sec whereas the subconscious is dealing with 20,000,000 bits of info every second.
Can your brain become overloaded?
Multitasking can overload our brain by increasing the production of stress hormones and triggering the fight-or-flight response.
Can your brain overheat?
Theoretically, the brain can overheat but not as a computer does. The reason is our brain harvests most of the energy produced with a relatively lesser amount being dissipated as heat. Our body has built-in cooling systems as well with continuous integration of all the processes, making the temperature control efficient.
How much RAM does your brain have?
2.5 million gigabytes
- 1953: Whirlwind computer debuts core memory | The Storage Engine | Computer History Museum. Computerhistory.org. (2022). Retrieved 26 January 2022, from https://www.computerhistory.org/storageengine/whirlwind-computer-debuts-core-memory/#:~:text=Led%20by%20Forrester%2C%20the%20Whirlwind,first%20time%20in%20August%201953.
- Bartol, T. M., Bromer, C., Kinney, J., Chirillo, M. A., Bourne, J. N., Harris, K. M., & Sejnowski, T. J. (2015). Nanoconnectomic upper bound on the variability of synaptic plasticity. eLife, 4, e10778. https://doi.org/10.7554/eLife.10778
- Can Your Brain Get Full? (Yes Or No?) – NeuroTray. NeuroTray. (2022). Retrieved 26 January 2022, from https://neurotray.com/can-your-brain-get-full/.