IB Psychology

Levels of Analysis — Options — Research Methodology — Internal Assessment — External Assessment

General Learning Outcomes

The general learning outcomes (GLO) at the biological level of analysis (BLOA) include all of the information that is within this level.

There are four general learning outcomes:

GLO1: Outline principles that define the biological level of analysis.
GLO2: Explain how principles that define the biological level of analysis may be demonstrated in research.
GLO3: Discuss how and why particular research methods are used at the biological level of analysis.
GLO4: Discuss ethical considerations related to research studies at the biological level of analysis.

Note that any example responses are not necessarily worth full marks, but exist simply to provide an idea of how an example looks.

GLO1

Outline principles that define the biological level of analysis.

This question was last asked in the November paper in 2014 specifying to outline two principles. The command term outline is a level one command term, and is asking you to give a brief account or summary. This outcome cannot be an essay, and is therefore worth 8 marks.

There are several principles that define the biological level of analysis. Such principles are:

Animal research can provide insight into human behaviour.
Biological correlates of behaviour exist.
Behaviour can be innate because it is based on genes.

Animal research can provide insight into human behaviour

This proposes that the results of studies conducted on the behaviour animals, can be extrapolated to human behaviour. For example, if rats are isolated from other rats and show depressive behaviour, it is likely that if humans were isolated from other humans they too would show depressive behaviour. This is possible because animals share genetic similarities, especially mammals, based on Darwin's theory of evolution. Rats in particular have a bilateral brain, as do humans, and developmentally human brains are very similar to those of rats. One of the primary focuses of the BLOA is to examine the behaviour of humans and animals. It is also more ethical to experiment on other animals, such as mice and rats, rather than primates. This is because primates are more closely related to humans (sharing 98.8% DNA) and have similar biochemistry. Hence, this principle defines the BLOA because it describes the relationship between the two behaviours.

Supporting Study: Martinez and Kesner (1991) was a key study that investigated the role of acetylcholine (ACh) on memory. The rats were trained to solve a maze and then, once they were successful, were randomly allocated into three conditions: rats that were injected with scopolamine (a drug that inhibits ACh levels), rats that were injected with physostigmine (a drug that increases ACh levels), and a control group. The rats were then sent through the maze again. The results showed that the scopolamine group had the slowest time and made the most errors, whereas, the physostigmine group was the quickest and mad the fewest errors. This shows that ACh plays a role in attention, concentration and learning, which aid in memory.

Link: Squire (1985) conducted a similar experiment, investigating the effects of ACh on Alzheimer's disease. He found that participants with lower levels of ACh concentrated in the hippocampus tended to develop Alzheimer's disease when they were older.

The behaviour is forgetting or Alzheimer's Disease.

Supporting Study: Rosenzweig and Bennet (1972) aimed to investigate whether environmental factors such as a rich or an impoverished environment affect development of neurons in the cerebral cortex. They assigned rats into two groups: an enriched environment (EE) and an impoverished environment (IE). The EE contained 10-12 rats which were put in a cage together and provided with different stimulus objects with which to explore and play; furthermore, they received maze training. The IE group had the rats situated in individual cages whereby they were isolated and given no stimulation. The rats typically spent 30 to 60 days in their respective environments before they were humanely euthanised. This was done so the researchers could study changes in the brain anatomy. The results indicated that the anatomy of the rat’s brains in the EE group were different to those in the IE group. The EE group’s brains had a greater density of the cortex. EE rats had developed more acetylcholine receptors in the cerebral cortex, which are important for learning, forward thinking and memory. The human behaviour which can be identified in the rats is brain plasticity. This is evident in the cerebral cortex which affects organising, planning, and higher order thinking; the frontal lobe which affects, personality and planning; and the greater development of acetylcholine receptors, which affects memory consolidation. It could be seen that the rats brains' in the EE group had developed as a result of their environmental stimulation (neuroplasticity).

Link: Maguire et al. (2000) investigated whether changes could be detected in the brains of London taxi drivers and to further investigate the functions of the hippocampus in spatial memory. 16 healthy right-handed male London taxi drivers were compared to 50 healthy right-handed males who did not drive taxis. The results were gathered using an MRI scan and the results were measured through Voxel Based Morphometry (VBM) and pixel counting. The first main findings of the research was that the posterior hippocampi of taxi drivers were significantly larger relative to those of control subjects and that the anterior hippocampal region was larger in control subjects than in taxi drivers. The second main finding was that hippocampal volume correlated with the amount of time spent as a taxi driver (positively in the right posterior and negatively in the right anterior hippocampus). Maguire et al. argued that this study demonstrates the plasticity of the hippocampus in response to environmental demands.

The behaviour is neuroplasticity.

Supporting Study: Olds and Milner (1954) used rats to determine the effects of stimulating the pleasure centre of the brain. The researchers found that rats would press a lever stimulating that centre repeatedly to the exclusion of other needs such as eating. Because a parallel structure exists in human brains, this research has been generalised to humans.

The behaviour is pleasure.

Biological correlates of behaviour exist

This means that for the physiological aspect of brain structures there is a behaviour associated with that structure. For example, the hippocampus is a brain structure that has a relationship with remembering. This defines the biological level of analysis (BLOA) because it investigates how the physiology of the brain affects particular behaviours, which is an integral part of the BLOA.

Supporting Study: Dr Barbara Wilson (1985) led a case study that investigated Clive Wearing. This study demonstrates a link between the behaviour of memory recall and the physiology of the hippocampus brain structure. Deborah Wearing, Clive Wearing's wife, provided permission for the study to be undergone and for his full name to be revealed. Clive Wearing contracted Herpes Simplex Encephalitis, which caused irreversible damage to his limbic system, and particularly the hippocampus. This led to both retrograde and anterograde amnesia, where retrograde means that he cannot recall some information prior to the onset of amnesia, and anterograde means that he cannot transfer short-term memory to long-term memory. This, in addition to his affected semantic memory, is demonstrated by his inability to differ between jam, honey and marmalade. Furthermore, his episodic memory is shown to have suffered when Clive Wearing is ten minutes into a conversation and can not remember how the conversation started, nor anything that was said ten minutes prior. Alternatively, his procedural memory appears to be functional as he can still play the piano, and additionally he has maintained emotional memory. Clive Wearing underwent Magnetic Resonance Imaging (MRI) scans which suggested that his hippocampus no longer exists, and he has sustained damage to his frontal cortex.

Behaviour can be innate because it is based on genes

Twin studies allow researchers to distinguish between nature and nurture influences on psychology.

Supporting Study: The Minnesota Twin Study aimed to investigate the concordance rates for a number of variables such as IQ, and it was conducted by Bouchard et al. (1990). The participants were white, middle-class monozygotic (MZ) twins from an industrialised nation, who had been reared together (MZT) and MZ twins who had been reared apart (MZA). The twins were measured by a standardised intelligence test called WIAS. Results from this test showed that the concordance rate for IQ was 69% for MZA and 88% for MZT. In conclusion, environmental factors do play a role in the development of intelligence but IQ is largely based on inheritance, and 70% of the observed variation in the sample could be attributed to genetic variation. The researchers claim that the results indicate that in a sample like the one in the study, genetic inheritance in IQ accounts for around two-thirds of the observed variance of IQ. They also said that their findings do not indicate that IQ cannot be increased, but that it is influenced by environmental factors.

Criticism: Scarr and Weinberg (1977) focused on parents who had raised both adopted and natural children. The assumption is that all the children had the same upbringing, in the same environment, with the same parents. Any significant differences between parent-child IQ correlations for adopted and natural children should be attributable to genes. The researchers found no significant difference in IQ correlations. This was very interesting, because in almost all the families in these studies, the adoptive parents were wealthy, white, and middle class, with high IQs, and the adopted children were from poor, lower-class backgrounds, with lower-IQ parents. Additionally, Horn et al. (1979) found similar results to Scarr and Weinberg, which refutes the findings of Bouchard et al.

Example response

There is no example response yet for this outcome.

Additional Notes

This outcome is very similar to GLO2 except that its focus is on the outcomes themselves as opposed to the research.

GLO2

Explain how principles that define the biological level of analysis may be demonstrated in research.

There are several principles that define the biological level of analysis. Such principles are:

Animal research can provide insight into human behaviour.
Biological correlates of behaviour exist.
Behaviour can be innate because it is based on genes.

Animal research can provide insight into human behaviour

This proposes that the results of studies conducted on the behaviour animals, can be extrapolated to human behaviour. For example, if rats are isolated from other rats and show depressive behaviour, it is likely that if humans were isolated from other humans they too would show depressive behaviour. This is possible because animals share genetic similarities, especially mammals, based on Darwin's theory of evolution. Rats in particular have a bilateral brain, as do humans, and developmentally human brains are very similar to those of rats. This is demonstrated in research such as...

Supporting Study: Martinez and Kesner (1991) was a key study that investigated the role of acetylcholine (ACh) on memory. The rats were trained to solve a maze and then, once they were successful, were randomly allocated into three conditions: rats that were injected with scopolamine (a drug that inhibits ACh levels), rats that were injected with physostigmine (a drug that increases ACh levels), and a control group. The rats were then sent through the maze again. The results showed that the scopolamine group had the slowest time and made the most errors, whereas, the physostigmine group was the quickest and mad the fewest errors. This shows that ACh plays a role in attention, concentration and learning, which aid in memory.

Link: Squire (1985) conducted a similar experiment, investigating the effects of ACh on Alzheimer's disease. He found that participants with lower levels of ACh concentrated in the hippocampus tended to develop Alzheimer's disease when they were older.

The behaviour is forgetting.

Supporting Study: Rosenzweig and Bennet (1972) aimed to investigate whether environmental factors such as a rich or an impoverished environment affect development of neurons in the cerebral cortex. They assigned rats into two groups: an enriched environment (EE) and an impoverished environment (IE). The EE contained 10-12 rats which were put in a cage together and provided with different stimulus objects with which to explore and play; furthermore, they received maze training. The IE group had the rats situated in individual cages whereby they were isolated and given no stimulation. The rats typically spent 30 to 60 days in their respective environments before they were humanely euthanised. This was done so the researchers could study changes in the brain anatomy. The results indicated that the anatomy of the rat’s brains in the EE group were different to those in the IE group. The EE group’s brains had a greater density of the cortex. EE rats had developed more acetylcholine receptors in the cerebral cortex, which are important for learning, forward thinking and memory. The human behaviour which can be identified in the rats is brain plasticity. This is evident in the cerebral cortex which affects organising, planning, and higher order thinking; the frontal lobe which affects, personality and planning; and the greater development of acetylcholine receptors, which affects memory consolidation. It could be seen that the rats brains' in the EE group had developed as a result of their environmental stimulation (neuroplasticity).

Link: Maguire et al. (2000) investigated whether changes could be detected in the brains of London taxi drivers and to further investigate the functions of the hippocampus in spatial memory. 16 healthy right-handed male London taxi drivers were compared to 50 healthy right-handed males who did not drive taxis. The results were gathered using an MRI scan and the results were measured through Voxel Based Morphometry (VBM) and pixel counting. The first main findings of the research was that the posterior hippocampi of taxi drivers were significantly larger relative to those of control subjects and that the anterior hippocampal region was larger in control subjects than in taxi drivers. The second main finding was that hippocampal volume correlated with the amount of time spent as a taxi driver (positively in the right posterior and negatively in the right anterior hippocampus). Maguire et al. argued that this study demonstrates the plasticity of the hippocampus in response to environmental demands.

The behaviour is neuroplasticity.

Supporting Study: Olds and Milner (1954) used rats to determine the effects of stimulating the pleasure centre of the brain. The researchers found that rats would press a lever stimulating that centre repeatedly to the exclusion of other needs such as eating. Because a parallel structure exists in human brains, this research has been generalised to humans.

The behaviour is pleasure.

Biological correlates of behaviour exist

This means that for the physiological aspect of brain structures there is a behaviour associated with that structure. For example, the hippocampus is a brain structure that has a relationship with remembering. This defines the biological level of analysis (BLOA) because it investigates how the physiology of the brain affects particular behaviours, which is an integral part of the BLOA.

Supporting Study: Dr Barbara Wilson (1985) led a case study that investigated Clive Wearing. This study demonstrates a link between the behaviour of memory recall and the physiology of the hippocampus brain structure. Deborah Wearing, Clive Wearing's wife, provided permission for the study to be undergone and for his full name to be revealed. Clive Wearing contracted Herpes Simplex Encephalitis, which caused irreversible damage to his limbic system, and particularly the hippocampus. This led to both retrograde and anterograde amnesia, where retrograde means that he cannot recall some information prior to the onset of amnesia, and anterograde means that he cannot transfer short-term memory to long-term memory. This, in addition to his affected semantic memory, is demonstrated by his inability to differ between jam, honey and marmalade. Furthermore, his episodic memory is shown to have suffered when Clive Wearing is ten minutes into a conversation and can not remember how the conversation started, nor anything that was said ten minutes prior. Alternatively, his procedural memory appears to be functional as he can still play the piano, and additionally he has maintained emotional memory. Clive Wearing underwent Magnetic Resonance Imaging (MRI) scans which suggested that his hippocampus no longer exists, and he has sustained damage to his frontal cortex.

Behaviour can be innate because it is based on genes

Twin studies allow researchers to distinguish between nature and nurture influences on psychology.

Supporting Study: The Minnesota Twin Study aimed to investigate the concordance rates for a number of variables such as IQ, and it was conducted by Bouchard et al. (1990). The participants were white, middle-class monozygotic (MZ) twins from an industrialised nation, who had been reared together (MZT) and MZ twins who had been reared apart (MZA). The twins were measured by a standardised intelligence test called WIAS. Results from this test showed that the concordance rate for IQ was 69% for MZA and 88% for MZT. In conclusion, environmental factors do play a role in the development of intelligence but IQ is largely based on inheritance, and 70% of the observed variation in the sample could be attributed to genetic variation. The researchers claim that the results indicate that in a sample like the one in the study, genetic inheritance in IQ accounts for around two-thirds of the observed variance of IQ. They also said that their findings do not indicate that IQ cannot be increased, but that it is influenced by environmental factors.

Criticism: Scarr and Weinberg (1977) focused on parents who had raised both adopted and natural children. The assumption is that all the children had the same upbringing, in the same environment, with the same parents. Any significant differences between parent-child IQ correlations for adopted and natural children should be attributable to genes. The researchers found no significant difference in IQ correlations. This was very interesting, because in almost all the families in these studies, the adoptive parents were wealthy, white, and middle class, with high IQs, and the adopted children were from poor, lower-class backgrounds, with lower-IQ parents. Additionally, Horn et al. (1979) found similar results to Scarr and Weinberg, which refutes the findings of Bouchard et al.

Example response

There is no example response yet for this outcome.

Additional Notes

This outcome is very similar to GLO1 except that its focus is on the research rather than the outcomes themselves.

GLO3

Discuss how and why particular research methods are used at the biological level of analysis.

Example response

There is no example response yet for this outcome.

Additional Notes

There are no additional notes yet for this outcome.

GLO4

Discuss ethical considerations related to research studies at the biological level of analysis.

Example response

There is no example response yet for this outcome.

Additional Notes

There are no additional notes yet for this outcome.

Levels of Analysis

Biological Level — Cognitive Level — Sociocultural Level

Biological Level

General Learning Outcomes

— Physiology and Behaviour

— Genetics and Behaviour