The link between brain and mental function
Much of what happens in the brain, in fact more than 80% of brain activity, occurs below the level of consciousness. We are never directly aware of this activity. Yet it is crucial to what we do become aware of. The role of the subconscious activity of the brain is to process and filter the vast array of information impinging on our senses and fed back from our behaviour (called brain function), and to decide what to pass on to our conscious minds for attention, thinking, decision-making and behaviour (called mental function). It takes the brain almost half a second to process new sensory or motor information, and to decide if any of it needs conscious attention. The information processed by our conscious brain is often retained as memories (learning), though the learning mechanisms themselves fall within the domain of the unconscious brain.
The information processing capacity of the brain is vast, employing the service of over 100 billion neurons. It is not possible for us to be aware of the activity of all of these neurons, or the complex and exquisite systems into which they are organized. However, the integrity of our mental world – the functioning of our mental systems – depends upon the integrity of the functioning of these underlying brain systems. If any of the brain systems fail or break down in some way, then our mental world can be fed with poor or incorrect information leading to psychological dysfunction. Psychological difficulties can also result, of course, from dysfunction of the mental systems.
Thus, psychological difficulties may have a number of different causes. Some derive from dysfunctional thoughts (mentally-based); some derive from physical abnormalities in the brain affecting brain or mental systems (neurologically-based); some derive from dysfunctional brain systems (functionally-based); some result from a mix of such causes, with causes in one category resulting in difficulties in one or more of the other categories.
Mentally-based disorders: as indicated, these are generally caused by dysfunctional (sometimes self-defeating) thoughts, beliefs, memories and attitudes. Thus, we may lack self-esteem, worry about the future, lack self-confidence, feel life is hopeless, hold irrational fears about things or events; and so on. Dysfunctional behaviour can result from such thoughts and make things even worse through the naïve responses of others. These sorts of psychological difficulties can often be resolved using cognitive therapy, that focuses on challenging and strengthening our thinking patterns, behavioural therapies that reverse the self-defeating behaviours that can result, or a mixture of both to normalize both thoughts and behaviour (cognitive-behavioural therapy).
Neurologically-based disorders: these result from damage to, or disruption and/or poor formation of brain tissue. They include open an closed head injuries, strokes, cysts, aneurisms, tumors and the consequences of genetic disorders affecting physical brain development. Their effect is to disrupt the functioning of the structure(s) affected, leading to some breakdown in the capacity of the brain to process information and in the related appropriateness (i.e. efficacy) of the resulting mental and behavioural function.
The initial assessment of the cause of these sorts of disorders is usually the task of a neurologist. However, it is important for the neurologist to work closely with psychologists and rehabilitation specialists in addressing the psychological and/or behavioural consequences of such disorders.
Neurological disorders can variously affect sensory, cognitive, affective, speech and digital motor function. Well known disorders include Parkinson’s disease, multiple sclerosis, Broca’s and Wernicke’s aphasias, Huntington’s disease, Alzheimer’s disease, cerebrovascular disease and many more.
Functionally-based disorders: functionally-based, psychological disorders are based on a breakdown of one or a number of the neural systems in the brain. These systems have various roles such as arousal and activation, attention, information processing (to identify objects and events – i.e. perception), learning and memory, and behavioural monitoring and control. There are also many other systems of more esoteric nature.
Breakdown of one or more of these systems undermines the capacity of the conscious mind to apprehend, and/or process objects and events, in a normal rational way. This can result in disorders related to the systems affected – learning, attention, arousal, information processing, memory and behavioural control. Such disorders cannot easily be treated using conventional psychological approaches such as cognitive and behavioural therapies – that involve modifying thoughts attitudes and associations. Rather, they are best treated by methods that directly address brain function itself – and preferably the systems affected.
The two main approaches to treating functionally based disorders is psychoactive medication and neurotherapy. Medication works by up- or down-regulating particular brain chemistry believed in a population sense to be a causal factor in a given psychological disorder. Medication, however, is relatively indiscriminate in the brain systems it targets and usually affects all parts of the brain, including those that may not be relevant to the disorder, sometimes resulting in side-effects.
Neurotherapy works by first identifying, at an individual level, dysregulated brain systems that are likely to be underpinning the presenting profile of symptoms. This is done using a brain function imaging method called QEEG, which measures the electrical activity of brain networks associated with attention and arousal, learning and memory, behavioural control, and mood and affect. Neurotherapy proceeds by retraining the es dysfunctional networks to normal levels with the aim of resolving the associated psychological symptoms.
Neurofeedback therapy, when indicated, can work well on its own. However, it is often valuable can work effectively with the temporary relief provided by medication. Depending on circumstances, it may also be necessary to combine neurofeedback with cognitive and behavioural therapies.
Note that assessment and treatment at Brain Health Clinics is concerned primarily with mentally- and functionally-based disorders. Any indication from assessment of possible neurological difficulties will result in the matter being referred to a neurologist.