Processing speed is an important skill of the cognitive system that allows the execution of various mental operations, ranging from seemingly simple perceptual abilities to highly complex problem-solving. Although some individuals perform faster than others, it has nothing to do with intelligence. It just reflects how fast a person can manage and effectively use information. Surely, we all would like to overcome our current processing speed and excel in our cognitive performance at work, studies or sports. The good news is that, far from having to repeat a task hundreds of times, there are new ways to get the brain to process faster and more efficiently. Today, the brain optimization phenomenon is not a question of imagination because scientifically it is already possible. But before considering increasing your processing speed, you may want to know how this technology really works in the brain and how realistic it can be.
What makes the brain perform fast or slow?
Understanding what causes fast and slow cognitive processing help researchers to find solutions to brain functioning deficits. Slow cognitive processing is initially attributed to a combination of neurochemistry alterations and a malfunction of certain brain circuitries. For example, some researchers have hypothesized that alterations of white matter integrity are related to processing speed deficits. Specifically, the white matter in the brain’s frontal lobe, which is the area that controls executive functions, is reduced in those with slow cognitive processing speed. Such dysfunction affects signals from passing between neurons as they normally do. Normal aging is another reason for cognitive slowing. Slow processing speed has been associated with greater pre-frontal cortex activation (PFC) for older adults but reduced PFC activation for younger adults. Although these changes are subtle, slow processing speed can be experienced in certain attentional tasks or when switching from one task to another. Studies have shown that at the age of 40, it becomes more challenging to quickly recall new information. Other factors such as stress, sleep disorders, and nutritional deficiencies have negative effects on the brain thus, causing slow cognitive processing speed.
Speed is not all, brain efficiency makes the difference!
The speed at which the brain process information entails a cognitive cost which is the number of neural resources spent to perform a task. Efficient brain performance involves a minimum effort of the cognitive system. When someone processes information fast but inefficiently, the level of accuracy decreases and the person experiences rapid mental fatigue due to an additional use of brain resources. Furthermore, the lack of fluent and efficient processing speed will slow-down all other brain functions and thus, the cognitive system will perform worse. When slow processing speed is not related to brain damage, one unanswered question refers to what causes some people’s brains to process information slower than others? The answer could be in the optimal use of brain resources. Research has shown that individuals with faster reaction time solving cognitive tasks have higher neural efficiency which entails better management of brain resources (see picture below).
Brainwaves at the spotlight
To better understand how to improve processing speed, for a long time neuroscientists have investigated the neural correlates associated with performance of elementary cognitive tasks. Current research uses electroencephalography to compare brain activity differences between fast and slow performers. One interesting aspect that we know already is that brain speed improvement is based on making more solid neural connections, which allows the signals to communicate faster between one another. Thus, the way people’s brain is wired and organized provides a hint of their processing speed. However, this is not enough to determine a causal relationship between a connectivity pattern and the level of processing speed. A more dynamic brain feature should be also considered to understand processing speed differences between the same range of age individuals. Besides the structural aspect, the brain is a dynamic system that generates bioelectrical activity known as brainwaves. Such brainwaves link to cognition, reflecting a unique pattern of synchronous activity oscillating in different brain regions at different speeds or frequencies.
Current scientific evidence provides reasons to believe an important role of brain oscillations in processing speed, specifically, the oscillatory activity of a frontoparietal network. It is known that such a network is variable between individuals. In a published study of Goldsmiths College London University, brain oscillations measured in badminton players and sedentary controls were compared during performance of a visuo-spatial processing task. When researchers looked into their brainwaves found that players – who responded faster than controls – exhibited a different pattern of oscillatory activity identified as higher beta desynchronization. In a recent study, researchers explored the oscillatory activity of a group of patients with processing speed deficits. Results showed that slow processing was related to an atypical frontal slow/fast oscillatory activity. Although these are very innovative results, they are not generalizable and more control conditions are needed to determine the specific oscillatory mechanisms controlling processing speed. The good news is that neuroscientists have already started to investigate different ways to improve processing speed and neural efficiency by directly affecting causally related brainwaves.
The emergence of neurostimulation devices
Innovative brain technology is emerging in order to improve cognitive functioning by directly affecting the neural plasticity. Non-invasive brain stimulation (NIBS) provides safe and relative low-cost methods to optimize cognitive functioning. Techniques such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), are being used already as a therapeutic option to treat various neuropsychiatric disorders with excellent results. In broad terms, these techniques deliver very low levels of a constant current to specifically targeted areas of the brain exerting an influence on their brainwaves. But… what about the speed of mental processing? Might it also work to make our brains to perform faster? The answer is yes because knowing the brain substrate – particularly brain oscillatory mechanisms – any cognitive function is a potential target for neurostimulation treatment.
To increase the speed of the brain with neurostimulation, researchers are testing both tDCS and TMS methods in healthy and cognitively impaired populations. The largest difference between how each technique work is that tDCS uses a sustained low-power current that changes brain plasticity up or down (see figure 1) while TMS makes the brain active with each pulse pattern application (see figure 2). The main predictions point to tDCS as the most readily available and cheap device to improve processing speed in children and adults experiencing slow processing speed. However, in the case of patients with severe cognitive impairment (e.g., depression, stroke, movement disorders, epilepsy, and pain) with associated symptoms of slow processing speed, predictions indicate greater benefits from TMS intervention given its brain region localization accuracy and high precision of stimulation.
The explosion in cognitive neuroscience is slowly revealing the mechanisms of brain processing speed. Today, the technology to improve brain cognitive speed is already available, albeit in an immature fashion. The future of brain stimulation therapies depends on a better understanding of brain biomarkers of each particular cognitive skill and disorders, alongside the development of better neuromodulation devices. This includes advancements such as better electrode design as well as computing approaches to acquire brain signals in real-time adapting stimulation parameters accordingly.