Biological Psychology

5.1 Introduction

The process of human biology and the passing of traits have long been studied throughout history. Understanding the impact of these processes on human behaviour is only one aspect of this research. Biological psychology is directed at adding to the understanding of human behaviour, within this context, which is the focus of this module.

Providing an understanding of biological psychology will be achieved by first exploring the basics of this field, namely how it is defined, history and persons of particular influence. Within this, the key features of biological psychology will be outlined. The theories of biological psychology and the discipline's strengths and limitations will also be covered before concluding with a brief section on the methodologies used to research this branch of psychology.

5.2 What is Biological Psychology?

The field of biological psychology is the branch that deals with physiological, or the physical causes of, behaviour. Sometimes alternatively referred to as biopsychology, psychobiology, or biological neuroscience, this form of psychology focuses on the relationship between the brain and the nervous system in relation to activities performed by either humans or animals. To do this, studies about mental processes and behaviour are conducted, which involve the application of the principles of biology.

Biological psychologists seek to understand how mental processes can provide valuable information related to other medical fields such as understanding various physical and/or mental disorders, or how to treat patients more accurately. They also attempt to understand what physical or anatomical attributes factor into certain behaviours.

Most biological psychologists research in specific areas. The themes that have been most prevalent within the field are: the control of behavioural systems; how movement and other human actions are controlled and coordinated; understanding the development of the nervous system in terms of behaviour over one's lifetime; the evolution of the brain and human behaviour; and understanding human sensory and perceptual processes. Topics related to similar processes within animals are also frequently studied, as well.

5.3 The Key Features of Biological Psychology

There are many topics that are the focus of biological psychology; some of these were noted in the previous section. Biological psychology seeks to understand how biology influences human behaviour, and this is done using five key areas of evaluation. These areas will be explored below. But before doing so, it is important to note that there are many similarities and links between each of them.

Adaptation

Adaptation, or in this case, psychological adaptation is a trait that benefits an individual in its environment. These traits can be of the functional, cognitive, or behavioural variety and can relate to any number of scenarios. Adaptations are usually the result of an historical need to solve a problem related to one's survival or ability to reproduce. Mating and morning sickness are examples of adaptation. When it comes to mating, both men and women have adapted certain traits to appeal to members of the opposite sex.

For example:

Women tend to be attracted to men who show signs of care giving and protection, whereas men are attracted to women whose hips are larger, as there is a belief that women with this shape perform better regarding child bearing. The latter is referred to as the hip-to-waist ratio. Men have also adapted a sense of humour as this is a trait that has been found to be appealing to women.

The second example is morning sickness:

This is sometimes also referred to as pregnancy sickness, although it tends to occur most frequently in the earlier hours, hence the name. The actual adaptation is said to be an internal mechanism to prevent pregnant women from consuming foods that may be toxic, or contain toxins that could harm the development of the baby.

Research shows that plant-based foods cause this reaction. There have also been studies that show a correlation between severity of morning sickness and the likelihood of having a miscarriage. The research indicates that women who experience the highest severity of morning sickness are less likely to experience a miscarriage. There is, however, some debate on the validity of this research.

Evolution and natural selection

Evolution and natural selection are most often associated with the works of Charles Darwin. Evolution refers to the processes that shape both the brain and body. It further relates to the change in specific biological traits that are passed on from one generation to the next. These processes promote biodiversity, as well. Natural selection, on the other hand, is a key component of evolution. It is the expression of a revised heritable trait over time. Adaptation takes place within this context, as well.

In this case, adaptations are the manifestations of natural selection. Therefore, the need to reproduce, and maintain the survival of the human species is reliant on the ability of an individual finding a mate. The examples given in the sub-section adaptation reiterate this.

Fact

According to a 2014 statistic, only 24% of Turkish people believed in evolution, whereas 80% of the population of Iceland did.

Source: Express 2014

Activity 1: Candy Dish Selection

Estimated time: 20 minutes

To complete this activity, you must have a bowl of different types of sweets (size, shape, flavour, etc.). This activity also works best if played with more than two people. The amount of sweets required for this activity depends on the number of people playing. A suggested number would be 10 per person. Have each participant pick a selection of sweets, until half of the original supply has been removed. Make a list of the sweets that remained in the bowl, and a separate one for those that were selected by the participants. Begin to list the traits of the sweets that were selected by the group members.

Once this list is complete, go through the same exercise for the sweets that are still in the bowl. The traits listed about the sweets remaining in the bowl are the ones that can be considered as the ones required to survive. Perhaps it was an undesired taste or texture that was a dominant trait in the unselected group, or something else. This is the basic function of natural selection - the traits that can survive the best, are the ones that will be passed on. The same is true with different plant and animal species, as well as within the realm of humans.

After the activity has finished, take a few minutes to consider a few questions:

Did any of the participants have more unique selections than the others, or did everyone tend to pick the same sweets?

What surprised you about the traits of the remaining sweets?

What real-life scenarios can you apply this activity to?

Heredity

he traits and adaptations that have been discussed in the above sub-sections are talking about the next feature of biological psychology - heredity. Heredity is the passing of traits from one generation to the next. This takes place through parent to child transmission. These traits can be physical attributes, behavioural, or otherwise. The biological study of heredity is called genetics. This is the branch of biology that seeks to understand how this takes place.

An example of heredity is body type:

If both parents are tall, there is a high likelihood that the child will also be tall. However, if one is tall and the other shorter, whichever parent manifests the more dominant set of genetics will determine the eventual height of the child.

Activity 2: Personal Trait Inventory

Estimated time: 10 minutes minimum

Take a few minutes to consider the concept of heredity and think about yourself. Using the checklist below, begin to identify which traits you have.

Allergies

Dominant hand (left or right)

Freckles

Able to roll the tongue

Hair colour

Eye colour

Type of hair (curly, straight, mixed)

Able to see the colours green and red

Hairline

Body shape

Wears glasses

Upon completion, spend some time considering the following questions:

How many traits did you have in all?

Were there any that surprised you, or that you had not realised was an inherited trait?

Which parent do you think you gain more of your traits from?

If you have siblings, do you think you share more traits than not?

To take this activity one step further, consider performing this activity in a group (minimum of five people; members of your family, for example). Use the information gathered in this secondary activity to calculate the frequency in which each trait is present in the participating group. This will show the traits that are most dominant within a random group, or within your family, depending on who you have participate.

Reductionism

Reductionism was covered in Module 3 on cognitive psychology. This was described as a way of taking a complex problem or scenario and breaking it down to its simplest form. To put it in more human terms, its means reducing a behaviour to a single cognitive process - even if there are other processes or influences taking place. This helps to understand what, exactly, is taking place, and how it can be changed to improve the behaviour. Looking at one specific gene to understand the hereditary traits of an individual is one example of this.

Sociobiology

Lastly, sociobiology is a field of study in biology that aims to explain evolutionary social behaviour. This is not unlike the processes involved in adaptation or natural selection - except that it is focused specifically on social changes. These behavioural changes include mating patterns, pack hunting and territorial fighting. Most of the research in this field has been applied to both human and non-human species. One of the dominant traits covered within sociobiology are instincts. Instincts are a set pattern of behaviour that are inherited.

They are usual in response to an external stimulus, but are naturally occurring. In humans, it is thought of as an intuitive response, or a pre-determined way of thinking, feeling, or acting. Fight or flight reβlexes, and the urge to procreate are examples of innate behaviours or instincts. That being said, instincts to a certain extent, can be overwritten, meaning it is possible not to act on them. There is conflicting data on this topic, however.

5.4 A Short History of Biological Psychology

Not unlike educational psychology, the biological branch also shares a limited history, due to its ties with other medical practices and research fields. However, the unofficial beginnings of biological psychology emerged throughout the 18th and 19th centuries. These initial contributions were linked with scientific - often medically associated - and philosophical research.

It was not until 1914 that the term 'psychobiology' was first used. Knight Dunlap published a text at this time entitled, “An Outline of Psychobiology,” which included research studies conducted by Dunlap. These studies shared Dunlap's work in the areas of the interconnection of mental processes and psychology. This was followed by another text, written by Edward Wilson under the title of “Sociobiology.” This text aimed at connecting evolution with psychology.

Outside of the aforementioned texts, some of the earliest studies in biological psychology covered the relationship between the numerous mental processes of humans, and their behaviours. They also widely focused on these same topics, but with animals as the centre of the study. As the field progressed, research began to tackle some of the most well-known diseases, including Alzheimer's, Huntington's, Parkinson's, and even Schizophrenia.

5.5 Important Contributors

Biological psychology has a wide range of significant researchers to credit. Many of its earliest contributors were not necessarily seeking to understand what is known as biological psychology, today, but rather to understand how the world works, and how human beings fit within it.

Charles Darwin

It may seem odd to find Charles Darwin (1809-1882) within the list of significant figures in the development of biological psychology. Best known for his studies on evolution and natural selection, and as being the author of the infamous “Origin of Species,” Darwin is certainly not often referred to as a key contributor to the field of biological psychology. However, his work on natural selection and evolution has been used as the basis for studies conducted on human behaviour and evolution, making Darwin a sound choice as an influencer of this field.

Darwin made the argument throughout his career that evolution was the result of inherited biological changes that occurred over time. While it is true that this does not necessarily relate directly to biological psychology, it is easy to make the connection of how this influenced early researchers seeking to understand how a person changes biologically over their lifespan.

William James

Known as one of the leading thinkers and most influential psychologists in American psychology, William James (1842-1910) had considerable training in physiology. This was a frequent occurrence for numerous early psychologists, but in the case of James, this was an important aspect of his career, and his influence of biological psychology. He wrote “The Principles of Psychology” in 1890, which discussed in great detail theory about human instincts. James believed humans had more instinctual tendencies than animals, and that they could be overwritten by new experiences and by influential interactions with others.

John B. Watson

John B. Watson (1878-1958) is often thought of as the father of behaviourism. He spent most of his career developing this theory and conducting studies on animal behaviour, as well as other human behaviours, such as child rearing, and the effects of advertising. His work on child rearing, is what makes him significant to the field of biological psychology, as his research helped to contribute to the understanding of the behavioural changes throughout infancy.

Roger Sperry

Roger Sperry (1913-1994), was a well-known neuropsychologist. He spent much of his career seeking to understand motor skills and sensory nerves, before winning the Nobel Prize in 1981 for his research on split-brain. Split-brain is a disruption in the communication between the two hemispheres of the brain. He also focused part of his career attempting to understand the differences of nature versus nurture.

Edward Wilson

Known as both the father of biodiversity and sociobiology, Edward Wilson (1929- ) has contributed to the discipline throughout his career. Many of Wilson's research focused on the social behaviours of insects - mainly ants - which he then attempted to apply to other animals, and eventually humans, as well. He reiterated much of Darwin's theory of evolutionary inheritance, citing that all behaviour is the result of heredity. It is these studies that have made Wilson a significant contributor to the field of biological psychology.

Fact

Edward Wilson is the leading expert on ants in the world

Source: NNDB 2014

Michael Gazzaniga

The final biological psychologist to be discussed is Michael Gazzaniga (1939- ). Gazzaniga is a leading researcher in the field of cognitive neuroscience, and has contributed to studies on the topic of human split-brain - the same area that Roger Sperry was interested in. His most notable study was on 'Patient W.J.,' a paratrooper during World War II that suffered from this phenomenon. Gazzaniga's work in this area has helped to develop a better understanding of how the brain works both in the face of split-brain, and as an ordinary brain should.

5.6 Concepts of Biological Psychology

When it comes to the theories and concepts of biological psychology most deal with the relationship between the body and mind. For the purposes of this module, four theories will be discussed: humanism, dualism, monism, and materialism.

Humanism

The theory of humanism stems from a philosophical worldview. It posits that the value and agency of an individual, or group of individuals, does not require the presence of a higher power in order to live by a set of ethics. It emphasises critical thinking, rationalisation, and empiricism over belief in a deity for the sake of believing. In other words, human beings can be good and live ethical lives, without the presence of a religion to guide the individual or group to be that way.

Dualism

Dualism is the belief that the mind and body are two separate entities. While they do function in conjunction with each other, they operate independently. This means that the mind - the non- physical, thinking, subconscious - does not require the body, or the physical mechanisms of the human makeup to function properly. Therefore, the recognition of the mental and physical attributes of an individual functioning despite the other is the main basis of this theory.

And, it is for this reason, that it is highly contested within the field of biological psychology, or biology more broadly. In dualism, the mind and brain are separate entities, as well. The brain is considered as part of the body, not the mind. This further complicates the understanding of dualism, as it seems impossible for this theory to be true.

Monism

This next theory is in complete opposition to dualism. Monism is a belief that the mind and body are one entity. It denies the possibility of a duality of any form, in terms of human functions related to the physical and mental components. In this case, the mind and brain are of the same entity, and that  brain functions within the human body, making it one being. There are different forms of monism, but in the context of biological psychology, it refers solely to the human makeup, and the processes that are required in order for an individual to function, physically and mentally. This is believed to be part of a survival mechanism, since both aspects work together in time of crisis, or other types of stress.

Materialism

Materialism is the final theory to be discussed. It is related heavily to monism. It states that the mind founded within the body. Materialism has philosophical origins, as well as that of biology, and even chemistry. The essence of materialism in relation to biological psychology, is that all things are made up of matter. This includes all things material, including the human body and all of its functions and processes. All aspects of the human body, including the brain, consciousness, etc., are all forms of matter, according to materialism.

5.6 Strengths and Limitations

Now that the theories and other components of biological psychology have been explained, it is important to think critically about the practice. This section will outline some of the positive aspects of biological psychology, while also highlighting some of its weaknesses.

Strengths

With the inclusion of the scientific application of biology, it is no wonder this branch of psychology is regarded as a highly scientific approach to understanding human behaviour. It is also highly applicable to other research areas and disciplines. The fluid nature of this area has helped to develop the field of comparative psychology, which is the study of the behavioural and mental processes of animals, and which will not be covered within this course.

There are also numerous empirical studies to support the theories that make up biological psychology. Biological psychology is also a beneficial practice, because it offers the opposing argument to the nature side of the 'nature versus nurture' debate. This is because the practice focuses on the natural tendencies of human beings, or the 'nature' aspect of human behaviour.

Limitations

In contrast to the noted benefits of biological psychology, there are several identified limitations of the discipline. To start, most of the experiments conducted in this field have a low ecological validity, much like other branches of psychology. It is also limited through the reductionist and humanism approaches. The latter, in particular, does not make way for free-will, which is something which readily showcases within the human makeup.

It is also widely believed that biological theories in psychology oversimplify many of the daily interactions that humans face within their environments. This is especially true when looking at the complexities within the physical aspect of human processes. It also does not recognise any of the cognitive processes, which is interesting given that they share several similarities in terms of their foundation and theoretical basis.

5.7 Methodologies in Biological Psychology

Biological psychology requires a lot of research in order to test its theories. Most of these studies are conducted in the form of lab experiments. This is because it would be difficult to test and track brain functions and other human traits without being in a fixed environment. It is also for this reason that biological psychology is noted as having a low ecological validity rating.

The basis for many tests and studies takes place using correlation. This form of research seeks to find linkages between topics, components, or any other aspects of human life in relation to behaviour and evolutionary changes over time. This reafβirms the need for lab-type experiments, or other methodologies that cannot provide accurate empirical results.

MODULE SUMMARY

This module explored the biological branch of psychology. It began by explaining that this field is the application of biological concepts to the realm of psychology. The key features of biological psychology were also discussed, which included adaptation, evolution and natural selection, heredity, reductionism, and sociobiology. A couple of activities were provided within this section in order to further develop an understanding of these concepts.

Following these sections, a synopsis of this field's history was introduced, along with a quick recap of several significant contributors, such as Charles Darwin, William James, John B. Watson, Roger Sperry, Edward Wilson, and Michael Gazzaniga. The concepts behind biological psychology were then described and noted as humanism, dualism, monism and materialism. Preceding the discussion of biological methodologies (lab testing and correlation) was a section on the strengths and limitations of this discipline.

It was noted that some of the strengths included the application of scientific methods as they relate to the study of biology, and the ability to examine animal behaviours as a means of understanding those of humans, while the limitations of this field were described as having a low ecological validity and an over simplification within its theories.