Information Processing In The Brain And Body – Are We Managed By And Do We Regulate Our Lives Using Discrete Units Of Information Rather Than A Continuous Flow Of Knowledge

I have been spending quite a bit of time at work since I started my current role as a Head of a Medical School two years ago trying to get data ‘dashboards’ together of all aspects of our business profile, so I can better understand our strengths and weaknesses, and make informed decisions on how to strategically improve what we do and how we do it. On the home front we are making some plans to change our living environment, and are gathering data to make the best possible decision before doing so with the information we have available to us. Most of my life I have been a research scientist, and generating and understanding data has been the ‘trademark’ of my working life. One of the major challenges left for science and us scientists to solve is the understanding of basic brain function and the brain’s capacity for dynamic regulation of the body’s activity. A major component of this endeavour is understanding how the brain responds to information flow from the body, how it analyses this information it receives, how it comes to a decision to act (or not act) based on this information analysis, and how it generates information flow back to the body in order in order for it to respond to and / or make changes as a consequences of these decisions. Most of the time life ‘feels’ as if it occurs in an ‘always happening’, linear, continuous manner, and there are no apparent ‘gaps’ in our conscious awareness of activities occurring either around us or in which we are ourselves functioning and required to make decisions about. But, us scientists when examining brain and body function, ‘break up’ the information we record from a research participant we are observing into discrete data units, using a variety of physiological laboratory assessment equipment, which are recorded and stored as such, and we later print these data out or put these recordings into spreadsheets as numerical data, and create line or bar graphs in order to understand and explain what we have observed. The question therefore arises if as part of the inherent brain and body regulatory mechanisms which manage our daily life activity, do we similarly understand and assimilate an understanding of activity occurring in and around us in such an information processing / discrete data based way?

One of the most pivotal moments of my research life was working with the peerless Neurologist Dr Bernhard Voller as a Research Fellow at the National Institutes of Health in Washington DC, fifteen years ago, when he showed me how to perform the technique of fine wire invasive recording of skeletal muscle activity (known as electromyography). When we had placed the electrode in a muscle (we examined the nerve firing in eye muscles for the particular experiment), and the subject blinked, one heard the firing of the nerves controlling the muscle via a speaker attached to the electrode recording device, and the rate of firing increased rapidly each time the subject blinked with greater force. What was such a ‘wow factor’ for me, was that what we were listening to was the information ‘code’ going down from the brain to the specific muscle we were studying, in order to make it contract with the required force. If you put a similar electrode into any nerve in the brain or travelling from the brain to the body, you will see or hear a similar firing rate change happening, which is the ‘code’ used by the brain to generate commands and induce changes in function of any organ the nerves target. One of the most interesting studies I have ever read looked at single neuron firing in the motor cortex of a monkey’s brain when its arm was being moved in different directions around its elbow joint. Each movement created a different ‘code’ of firing which was unique to each specific movement, and if one looked at the graph plots of the generated data after learning the different ‘codes’ for each movement, one could predict with a high degree of certainty which arm movement had occurred to produce each specific trace. So certainly at the physical nerve firing level, information is generated, and function regulated, by discrete coded information that was evident and could be ‘decoded’ when examining a particular nerve’s firing rate.

This numerical coding of information is also evident across a variety of body systems. For example, heart rate is a measure of how fast the heart beats, and we know that when the heart beats faster it is working harder in response to a greater need for blood flow around the body, such as when doing exercise, or during a hot day, or when one is sick and has a fever. So if we examine a heart rate trace collected during a 24 hour period of time from someone, without being told what the person whose heart rate we were retrospectively examining had been doing, we could make a good guess of what activities the person had been involved with at different stages of the time period their heart rate was assessed. For example, if the heart rate is very high for an hour or two in the early morning or evening period, one can assume with a high degree of certainty that this is probably caused by the performance of a bout of exercise. In contrast, if heart rate is very low for an extended period of several hours in the evening time, one can guess that this would be associated with a period of time when the participant was sleeping. Another very interesting study for me was one that examined the output of neurotransmitters (a chemical substance) when a varying change in firing rate was artificially induced in a neuron ‘upstream’ of the synapse where the neurotransmitter was released, and it was found that the release of neurotransmitter occurred in a discrete pulsatile manner that was directly correlated with the ‘upstream’ induced firing rate. This indicates that the ‘fidelity’ of the rate coded neural message was maintained even by chemical substances, and that regulatory information is not confined in complexity or content only to neuronal firing mechanisms, but occurs also in blood borne / neurochemical substrates.

In order for this ‘rate coded’ information to be created and interpreted, some yet unidentified algorithmic processes in the brain needs to break it up into ‘useable’ bits or chunks of information of a certain length or period of time, and the interpreting algorithm needs to have a ‘pause’ in order to both make sense of this information and respond to it, before ‘receiving’ and responding to further information from the same source. If information arrived in a continuous stream that was not ‘broken up’ into ‘bits’ of information, no interpretative sense could be made of it, and no logical response based to the information encoded in it could be initiated. We have previously suggested that information must occur as, or be broken up by the brain into, ‘quantal packets’ of information, and each ‘quantal packet’ of information is used by the brain to make sense of what is required by whatever initiated the perturbation that lead to the generation of the information flow, and how the brain needs to respond to the information. There is surely always alternating periods of ‘certainty’ and ‘uncertainty’ occurring related to the flow of information in the brain and body – certainty when a coherent quantal packet of information is received and ‘understood’, and uncertainty in the periods prior to the full required quantal packet of information being received, or during the period after the full quantal packet of information was received and a response to it enacted, during which time and after which further information from the original source will be required to assess whether the response was satisfactory and / or fulfilled the need that caused the original information to be generated. So the passing of time is a fundamental requirement of information flow and the understanding of it, and there will always be alternating time periods of certainty and uncertainty related to the information flow. What length of period of time or quantity of information is required to create a period of certainty in any brain or body system is likely to be a product of the type of substance which creates the information (ie shorter in nerve tissue and longer in humoral / blood substance), what purpose the information is created for, and the complexity of the issue the information is associated with.

Clearly from the above examples, a strong case can be made that information coding underpins the regulation of physical brain and body function. However, it is more difficult to understand how cognitive (mental) information we receive from the external world is ‘managed’, and if and how we ‘break it up’ into useable ‘bits’ of discrete information that can be made sense of by our algorithmic information processing functions of the brain. Most data would suggest that we do indeed break up information of social or environmental situations into at least categorical (for example need to respond / not respond) information. My esteemed colleague at the University of Worcester, Andy Renfree, has looked at decision making theory in relation to physical activity and shown that we make cognitive decisions on future levels of activity or plan for future activity based on either rational (taking all factors into account) or heuristic (using past experience to attenuate the complexity of decision making requirements) information and cognitive decision making, using differentiated information about one’s own current physical capacity and performance level, environmental factors, and the capacity of other individuals one is competing against, amongst a number of other factors. Knowledge of all possible behavioural outcomes, and an assessment of the potential risks to oneself of all the potential outcomes, as well as their potential rewards, are surely also individually assessed as part of any action related decision making process. However, cognitively and consciously it never ‘feels’ that all such factors are so individually and discretely assessed, but rather that life occurs as a ‘smooth’, continuous activity, with no perceptual ‘gaps’ occurring when decisions are being made or when cognitive uncertainty must be occurring. This ‘smooth’ conscious perception of life with no ‘gaps’ in it may occur because we do not focus on a specific thought, activity or sensation for any extended period of time, and rather ‘switch’ our attention continuously between different issues we are ‘working through’. Therefore, as a number of different thoughts related to different issues ‘intrude’ sequentially on our consciousness, this may ‘fill the cognitive gaps’ which would occur as a necessity when making cognitive decisions on any one specific issue or requirement, in the time periods of uncertainty before a cognitive ‘decision’ is made about any one ‘issue’ one is dealing with. It is obviously very difficult to research this area of cognitive information processing, given our lack of knowledge of core brain function, and the difficulty of being able to objectively assess one’s continuous real-time thought processes with the current laboratory research techniques available to us, which are still very crude and retrospective / mostly qualitative in nature.

While life as we know it may thus appear to occur as a continuous flow of activity and events which we respond and react to, how we interpret these activities and events and regulate our responses to them may indeed occur in a discrete information based numerical manner, replete with information ‘gaps’ and periods of uncertainty interspersed with ‘quantal packets’ of information rich certainty time periods, that each vary in length dependent on the complexity of the situation being assessed, the processes being used to assess it, and the physical substances in the brain and body used to assimilate and understand them. Information processing and decision making underpins all regulation of our brain and body functions and our successful interaction with the socially and environmentally challenging external world in which we exist. Our successful reaction to changes in either external environments or our internal physiological milieu depends on the successful generation of information describing these changes, the successful interpretation of this information, and the successful generation of actions in response to this information. At the neuronal level simple firing rate and rate coding underpins all information flow, and our physical responses are related to changes in this ‘code’ and the information encoded by these firing rate changes. To better understand the manner in which this information processing occurs in more complex issues is a lifetime of work in the time ahead for us neuroscience and information science folk. But, perhaps us scientists use discrete numbers and data to makes sense of how things work, because at the level of brain and body regulation and control, information flow and discrete data generation and assessment are the conceptual requirements underpinning all successful life activity, and us scientist folk are merely copying the ‘instruments and methods’ of the master designer who created us in the way we have been created when we do such work, whatever that master designer is or was. Time will tell if this is true or not, but, pertaining to our domestic decision-making requirements relating to whether we should stay in our current environment or move to another – brain neurons, was that one click or two I heard when you fired as I was thinking on this issue a moment ago!

Advertisements

About Alan (Zig) St Clair Gibson

Professor Alan (Zig) St Clair Gibson MBChB PhD MD - Dean of the Faculty of Health, Sport and Human Performance, University of Waikato, New Zealand View all posts by Alan (Zig) St Clair Gibson

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: