Woman in the car
Sequential memory is a manner of remembering and processing information, and is is central to how we go about our everyday lives. Image Credit: Pexels.com

The house is green.

House the green is.

You would have instantly caught on to the incorrect sequence of words in the second sentence. Your brain knows when something is off. This is owing to how you mastered language and grammar. Another example would be driving. You won’t just get inside the car and randomly steer the wheel without starting the engine, now would you? There’s a sequence to follow; your brain knows it.

These are all examples of sequential learning and processing, a trait that is particularly advanced in humans. According to a recent study, even the bonobos, the closest relatives to humans do not possess this ability of memory and cognition. This helps with solving the puzzle that scientists have been trying to tackle for years: Why humans are the most evolved, compared to other species.

What does research say?

Man teaching children
This skill is fundamental to various activities, from language development to advanced planning and social interactions Image Credit: Pexels.com

How have humans created societies, navigated space travel, seen technological advancements, and raced culturally ahead of other species? A part of the rather complicated answer lies in this particular cognitive function of sequential processing. This manner of remembering and processing information is central to how we go about our everyday lives. It’s why we can participate in conversations, go to work, plan our routines and have an education. Possessing a sequential memory is a crucial, underlying block of many human behaviours, say experts.

In the recently published book, The Human Evolutionary Transition: From Animal Intelligence to Culture, ethologists Magnus Enquist and Johan Lind at Stockholm University, and Stefano Ghirlanda, explained why humans became cultural beings, through a series of experiments. The most crucial idea is in how both humans and animals recognise and remember sequential information. In their earlier studies, the team had analysed that as compared to several mammals and birds, humans possess the ability to recognise and remember sequential information correctly.

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Compared to several mammals and birds, humans possess the ability to recognise and remember sequential information correctly. Image Credit: Pexels.com

The memory abilities of bonobos (apes) and humans were tested in a series of experiments, where they had to press computer screens among other things. They had to distinguish between short sequences, including pressing right, if a yellow square comes before a blue square, or by pressing to the left if the blue square appears before the yellow square. In this experiment, the bonobos forgot that they had seen the blue square five to ten seconds after it disappeared from the screen. They had great difficulty in learning to distinguish the blue square before yellow square from yellow square before blue square sequence, despite being through over a thousand trials, one of the researchers had told Neuroscience.com.

On the other hand, humans distinguished the short sequences immediately. These new findings bolstered the belief in the theories that the ability to remember and process sequences have evolved since human prehistory. This is now seen to be a rather distinct trait for humans, which is seen in their language, planning ability and sequential thinking. It could also be the reason behind the origin of human culture, says the research.

What is sequential information processing?

Person reading
Learning a language is a form of implicit sequential learning. Image Credit: Pexels.com

The word ‘memory’ usually leads people to believe that it is an all-encompassing memory, when in fact, there are different kinds of memory. In the case of sequential memory, it is the ability to recall things in a specific order. “Sequential information processing is an essential cognitive function,” explains Ovgu Ozturkeri, neurologist at the German Neuroscience Center, Dubai. This could be the way we learn the days of the week, the months of the year, and counting. Visual sequential ability is how we remember things seen in sequence, and auditory sequential ability is the ability to remember things heard in sequence.

Ozturkeri explains that this processing is deeply rooted in the key brain areas such as the hippocampus, which manages long-term memory and navigational abilities, and the prefrontal cortex that manages our thoughts, actions and emotions. The growing study of this trait helps to contribute to understanding cognitive differences between humans and animals, and there’s still much research on why only humans possess the ability for language and planning.

But is this actually unique to humans? Ozturkeri asserts that the ability itself isn’t unique in humans, as rats can navigate complicated labyrinths, but humans stand apart owing to the complexity in which they handle such information. “This skill is fundamental to various activities, from language development to advanced planning and social interactions,” he says. Rather than calling it “unique” to humans, she maintains that it is far more advanced in humans than other species.

Implicit and explicit sequential learning

How did we learn driving? How is it different from the way we learned a language?

Upasana Gala, a neuroscientist, founder and CEO of Evolve Brain Training Dubai, breaks the process down further. “The process for sequential learning involves encoding information, storing it, and then reproducing it in order. The information is acquired, stored away and then the knowledge is used,” she says. There are two types of learning, which is implicit and explicit. In implicit learning, you perform a task repeatedly and gradually improve your performance without being conscious of the rules or principles underlying the task. You learn complex information without being aware that you are learning it. For instance, learning a language or recognising faces.

The process for sequential learning involves encoding information, storing it, and then reproducing it in order. The information is acquired, stored away and then the knowledge is used...

- Upasana Gala, founder and CEO of Evolve Brain Training Dubai

When it comes to explicit sequential learning, we are trained, taught and then we remember, she says. We are aware of this learning. This would be the way you drive, or learn dancing, singing or any musical instrument. These intricate cognitive processes are what lead to creation of cultures and societies, she says. Human beings are far more advanced in terms of cognitive functioning and planning, whereas animals live from moment to moment, she says.

What happens when sequential learning is impacted?

However, it's worth noting that people who find daily activities like planning or conversations particularly challenging might require a neurological evaluation, says Ozturkeri.

Conditions like Attention Deficiency Hyperactivity Disorder and dementia can impact this important cognitive skill, making what should be routine tasks more difficult. These evaluations can provide both diagnostic insights and potential paths for cognitive improvement

- Ovgu Ozturkeri, neurologist, German Neuroscience Center, Dubai.

“After all, conditions like Attention Deficiency Hyperactivity Disorder and dementia can impact this important cognitive skill, making what should be routine tasks more difficult. These evaluations can provide both diagnostic insights and potential paths for cognitive improvement,” she says. Here, the person would find it difficult to read, retain information properly in the memory, and cannot hold a cogent conversation for a long time. This could be related to hippocampus damage or some other neurological damage. Sometimes it is reversible or further damage can be halted with exercise, diet and the right therapy or medication.