What does an understanding of biological processes offer to psychological explanations
By studying the brain we can conceive hypothetical structures of personality making predictions of behavioural outcomes, through an outsider and insider viewpoint. Technological advancement can reveal brain abnormalities and understand the chemical activity of brain cells. Gaining a clearer understanding of psychological brain processes and their determents of behaviour.
(Francis Crick 1994) a biologist claimed all psychological events could only be explained in brain activity. Social phenomena, explained in terms of genes and biology of the brain. Known as reductionism, it offers two theoretical approaches. Psychological phenomena could be explained through the framework of the basic sciences and simple principles such as stimulus and response associations. These brain sciences can be organised in a descending hierarchy with the more generalised at the top and the complex tapering at the bottom.
(Bolton and Hill 1996), made a counter claim that many psychological phenomena cannot be reduced to physiological or biological terms. Psychology is concerned with processes, whereas physiology is structure. This eclectic approach leans towards biology and psychology being reciprocal.
When brain and mind are combined they form an emergent property, something not evident when looking at components individually. Behavioural phenomenon arises from physical brain interaction and the minds interpretation of the social environment.
The brain comprises of neural chemical pathways. Mind, is philosophical even spiritual. Rene Descartes (1596-1650) claimed that a stimulus could initiate an almost mechanical reflex action. Descartes analogy drew on technology of his day envisioning a human mechanical machine in which levers, gears and hydraulics led to bodily actions. Termed dualism- a philosophical perspective that draws an absolute distinction between brain and mind.
Scientists reject the idea that mind can exist physically from the brain. A key feature remains; mental processing can be termed using an engineering analogy, where energy is transposed either electrically or chemically into the end result of bodily movement. Psychologist’s interests lie with neurons and synapses these form part of the nervous system. Variations in the functioning of this system can be associated with differences in behaviour and the mind.
The synapse is the junction between neurons; it is thought that an abnormality in a number of synapses in the brain may be the root of psychological disorders. Chemical transmitters pass messages across the synapse. The synapse like a switch operates in one of two states; excitation the message continues across the synapse to the next neuron, or inhibition the activity is suppressed and no message is passed. Schizophrenia may be associated with abnormalities within certain types of neuron transmitter. Parts of the brain may be abnormally active and people’s attention may be drawn to stimuli usually ignored.
Mood, behaviour and emotions all stem from the level of activity of neurons in the brain, resting with the synapse. A change in synaptic level will change the level of neural activity. Change could be orchestrated through many mediums such as Parkinson’s disease, caused by the loss of dopaminergic neurons. Prescription drugs like the depression countering Prozac, which target specific synapses. Non-prescriptive drugs, nicotine, heroin and cocaine, alter the activities of synapses. When a neurotransmitter is released across a synapse a corresponding transmitter takes it up. Excess neuro transmitters are cleared from the synapse junction after reception by receptors. Neurotransmitters are dismantled by enzymes or recycled back across the synapse into the presynaptic synapse by special re-uptake receptors.
Cocaine inhibits reuptake of dopamine in the neural system. The remaining excesses of dopamine, accentuates euphoria. The down side, as reuptake is blocked dopamine is not recycled, ultimately leading to depletion of the neuro-transmitter leading to dysphoria. Drugs don’t just work in isolation but need to be viewed in terms of the whole nervous system and conscious awareness. Different drugs will have different effects, the environment can also shape a persons interpretation of effects. Due to anxiety and environment they are experiencing, habitual users, taking a placebo may also feel an effect.
(Sperry 1969) pioneered a procedure that successfully absolved epilepsy, involving cutting through the corpus callosum. There were however consequences regarding the interpretation of information through the right hemisphere. (Penfield and Rasmussen 1968) studied conscious patients undergoing surgery they were asked to give reports on the sensations they received through electrical stimulation of the temporal lobe. Patients claim to recall vivid memories of incidents earlier on in their life. This evidence leads to the biological relationship of memories to a specific area of the brain.
One of the most famous cases was the evidence drawn between brain and behaviour (Phileas Gage 1848) a tamping iron passed through his skull piercing the left hand frontal lobe. In the aftermath Gage didn’t inhibit much impairment in his speech or his intellect. Later, he became obstinate, capricious and egocentric. These findings led to the conclusion that emotional expression was controlled by this part of the brain. Evidently the damage had released the inhibitions controlled by the frontal lobe.
The problem with this evidence is that it is isolated and uncontrolled and rarely limited to one specific part of the brain. In addition the damaged part of the brain may be superseded by another part of the brain.
To summarise biology and psychology have a reciprocal relationship, there are some hardliners like Crick, who state the brain is solely responsible for psychological activity. Conversely Bolton and Hill repudiate reductionism and claim that psychology can’t be just biology and physiology. Descartes claimed that there was a true distinction between brain and mind coined dualism and it was a stimulus that created a bodily reaction. Scientist have dispelled that theory but
hold firm the analogy of stimulus transposed through chemical/electrical action to create a response. We have made a clear discovery that it the synapses shape our behaviour and abnormalities in this neuro transmitter provide proof that they are responsible for psychological disorders like schizophrenia. Prescription drugs can provide chemical therapy in the shape of Prozac for depression or obsessional neurosis. Non-prescription drugs like Cocaine, block reuptake of dopamine in the neural system leading to drug dependency. Finally we have explored research carried out by Sperry, Penfield and Rasmussen and the after effects of Phileas Gage accidental brain lesion.
In conclusion Psychology and biology underlie all behaviour. What happens when a person witness’s a shocking image like a car crash? The physiological explanation would be the ambient light reflected forming an image on the retina that is converted into a neural signal and transmitted to the brain. Conversely a psychological explanation may draw on the personal and social relevance of the experience that many would argue is of greater value.