1) Compare and contrast the nativist and neuroconstructivist positions of brain development. What implications does the neuroconstructivist model have for atypical development? Why is developmental timing so important? (6 points)
The nativist and neuroconstructivist positions of brain development differ in several ways. The nativist approach of brain development highlights that humans are born with pre-set structures which we then use in order to develop. In this view, the environment is merely a trigger for the activation of these preset structures (Karmiloff-Smith, 1998). This approach focuses on prenatal growth. On the other hand, the neuroconstructivist position of brain development is that development is the outcome of interactions between genetics, the brain, cognition, and the environment. While they do acknowledge the role of prenatal growth, they view the environment as playing a significant role in shaping and specifying brain structures (Karmiloff-Smith, 1998). In terms of an evolutionary perspective on brain development, nativists suggest that evolution is what has led to a more pre-specialized neocortex whereas neuroconstructivists see evolution as the force adapting the neocortex in order for individuals to have a greater capacity to respond and learn throughout development (Karmiloff-Smith, 1998).
Although these two approaches vary greatly, they do share some similar views. The nativist and neuroconstructivist approaches both view development as continuous and ever-changing, with the environment being an important factor (Karmiloff-Smith, 1998). The importance of the interaction between the child and the environment is acknowledged in both approaches. The way the child reacts and processes their own environment is going to affect their own development. Both approaches acknowledge the effect the child has on their environment and vice-versa (Karmiloff-Smith, 1998). With the child having an active part in choosing their environment, this leads to the gradual development of domain-specific representations. Development of domain-specific representations indicates independence of brain structures, while also a specialization of certain structures (Karmiloff-Smith, 1998). Individuals are able to train one area of the brain without it affecting other areas. Both approaches do agree that development involves influences from both the environment and genetics (Karmiloff-Smith, 1998).
The nativist approach suggests that disorders are the cause of innate impairments to domain-specific cognitive modules (Karmiloff-Smith, 1998). It is the belief that these impaired modules are there from birth and that atypical development stems from a genetic cause. Due to the atypical deficit in the brain circuit, plasticity is the brain’s response to that innate deficit, causing developmental disorders (Karmiloff-Smith, 1998). The neuroconstructivist approach argues that there are some innate starting points but that overall, modules emerge over development and are not solely innate. Plasticity is then in response to input the brain receives from the interactions with the environment. As Dr. Kelley discussed in lecture, this approach credits that disorders are not as specific and lie more on a continuum.
As we have learned in lecture, atypical development has widespread effects. As it affects the brain, this leads to many neural and behavioral issues. The neuroconstructivist approach on atypical development implies that abnormalities occurring in lower levels actually have flowing effects on other parts on the brain as well (Karmiloff-Smith, 1998). As the brain constructs itself, functional specialization on modules that occurs for typical children may not occur for atypical ones. This suggests that with the interaction of these cascading effects of interacting genes and environment, it is a cascade of several subtle deficits rather than one large higher level one (Karmiloff-Smith, 1998). This approach is more indirect and seen as lower level causes rather than directly impaired cognitive modules (Karmiloff-Smith, 1998).
The neuroconstructivist model focuses on change and emerging outcomes, unlike the nativist approach. The neuroconstructivist approach views every interaction and aspect of development as interactive and ever-changing. It considers domain specificity to not be the starting state but rather the outcome of development (Karmiloff-Smith, 1998). Therefore, the downstream effects of interactions between genes and environment suggest that atypical development may be caused by many things as behaviors can be reached by many different pathways (Karmiloff-Smith, 1998). This implies that there must be more of a continuum of developmental disorders rather than one clear cut disorder as there can be a failure to specialize or develop many modules.
As learned in lecture, developmental timing is one of the most important factors that need to be taken into account when considering human development. The developing brain interacts differently with other parts across development, so better understanding the timing of the deficits can help us to better understand the mechanisms that have gone wrong in that impaired domain (Karmiloff-Smith, 1998). Atypical timing across developing systems can cause discomposure in many basic processes very early on in development. The developmental timing is so important because domain-specific outcomes may not be feasible without the steady course of development over time (Karmiloff-Smith, 1998). To fully assess developmental outcomes and trajectories of different developmental disorders it is crucial to understand the progressive changes from infancy and onwards. The developing brain interacts differently with other parts across development, so better understanding the timing of the deficits can help us to better understand the disorder.
As Dr. Kelley mentioned in class, developmental timing is also important because it allows for earlier treatment when caught at an earlier stage. It is crucial to study disorders in infants as the earlier the genetic impairment, the more widespread it will be in the neocortex (Karmiloff-Smith, 1998). This can create differential outcome effects. If certain structures are neglected early on in development, this can lead to later difficulty developing other structures, leading to atypical development. This is why it is important to catch atypical development earlier on than later. Studying these early markers for disorders is beneficial for better treatment and understanding of the disorder (Karmiloff-Smith, 1998).
2. The National Institute for Mental Health in the United States (one of the largest funding bodies in the world) has proposed that researchers should stop our focus on investigating individual disorders but rather look for endophenotypes that can be seen across disorders, and investigate their genetic associations and response to treatment. Do you agree with this assertion? Why or why not? Would development itself have an effect on endophenotypes? (4 points)
When considering newly proposed psychological theories, it is important to regard both the advantages and disadvantages in order to confirm that the approach is accurate and appropriate for studying mental disorders. In terms of focusing on endophenotypes across disorders, their genetic associations and response treatment, it is crucial to look into every aspect of this approach before coming to a final decision. There are valid arguments both for and against the endophenotype approach proposed by the National Institute for Mental Health in the United States (Insel & Cuthbert, 2009).
Insel and Cuthbert (2009) discussed how it can be challenging to determine the underlying mechanisms behind certain disorders since there are many overlapping symptoms (Insel & Cuthbert, 2009). This approach introduces using clusters of symptoms across disorders rather than categories of disorders which will help to address some of this confusion (Insel & Cuthbert, 2009). A plus side to the endophenotype approach is that since they are reliably measured, they may help to identify predisposing genes for complexly inherited traits. With the description and definition of the endophenotypes for common disorders, this can tell us several features for genetically analyzing and better treating these disorders (Insel & Cuthbert, 2009). Since disorders are caused by numerous environmental and genetic factors, using endophenotypes would be helpful to form links between mental disorders which can help to suggest prevention strategies (Insel & Cuthbert, 2009).
The endophenotype approach will also help to better understand the underlying mechanisms of the disease which will then further provide treatment options. Since the genes influencing mental disorders are bound to show up on multiple neural systems, this makes it more promising for these genes to be found across patients and gives us a better understanding of what mechanisms are dysfunctional for a given disorder (Insel & Cuthbert, 2009). When endophenotypes are identified accurately, they will help to provide reliable and measurable characteristics of the disorder. Better understandings of the causal mechanisms of disorders will allow for the improved design of treatments directed at the disorder.
As we see, there are some clear benefits to the endophenotype approach but there are also some drawbacks. One major issue with this approach is the lack of attention to the child’s environment. Endophenotypes do not successfully take into account the environment of the child of the child’s character. As the approach does not account for the variability of the child, which is a key component when studying atypical disorders, it leads to inaccurate conclusions (Insel & Cuthbert, 2009). For example, ADHD children may have different reaction times due to their environment because they struggle with getting distracted. Autistic kids may not care enough about the task or pleasing the experimenter, which will cause variability in reaction times as well. Kids with Down Syndrome may not be as fast at completing the task, due to actual brain deficits (Insel & Cuthbert, 2009). These examples could all cause for variability in the reaction time, which is why it is important to factor in the environment of the child. The issue with the endophenotype approach is that it does not account for environmental factors and as we have learned in the lecture, we know that environmental factors are just as important as biological ones.
As we have learned in class, development is a product of both nature and nurture so it would be impossible to separate our endophenotypes from our development. Neither the environment nor our genes can be disregarded when considering developmental disorders. The environment plays a significant role in the development of disorders and as well when considering the proper diagnosis and treatment plans (Insel & Cuthbert, 2009). Therefore, solely using the endophenotype approach to mental disorders would be simplifying them solely to a genetic perspective, which would be fully disregarding all environmental factors.
3. Discuss the history of how psychopathology has been viewed over the last century or so. Why does cognitive neuroscience offer a better perspective? What does cognitive neuroscience still need to add to be able to better describe developmental disorders and why? (5 points)
Freud’s psychoanalytic theory has been dominating the field of psychiatry for the last 50 years. The Freudian theory focuses on early relationships and development and the importance of those early stages. Within psychiatry today, biological psychiatry has mostly replaced the Freudian theory (Pennington, 2002). However, even with both cognitive-behavioral psychology and biological psychiatry, we still lack a complete theory for fully understanding psychopathy (Pennington, 2002). The struggle is whether to focus on studying the brain or the behavior. Current psychological theories seem to deal with the social contexts that are shaping the development of psychopathology but are missing the underlying mechanisms that account for individual differences and seem to ignore the brain (Pennington, 2002).
Cognitive neuroscience is an emerging phenomenon that offers a new perspective within psychopathology (Pennington, 2002). This theory is concerned with the underlying biological processes of cognition. This approach suggests that the disruption of many brain and body conditions can generate psychopathological disorders (Pennington, 2002). It focuses on the reduced key physical components of behavior and cognition. It also discusses the nervous system, and the interactions at this lower level of componentry units can be connected to behavior and cognition (Pennington, 2002). This approach is combining aspects of both biological and psychological explanations of disorders to provide a deeper understanding of mental illnesses and allowing a more collective approach to psychopathology.
Unlike much of biological psychopathology, cognitive neuroscience is committed to both physical reductionism and reconstructionism (Pennington, 2002). Understanding components of cognition in terms of their molecular biology is helpful but will not be able to explain alone what causes complex behaviors. The interactions at elementary unit levels to understand cognition and behavior is also crucial for a deeper functional understanding of cognition (Pennington, 2002). Cognitive neuroscience integrates both of these models in order to attempt to explain complex behavior. As we discussed in lecture, using both of these models can help to have us have a deeper understanding of the interactions at a neuronal level and as well as behavioral and cognitive levels (Pennington, 2002). Through cognitive neuroscience and psychopathology, we are better able to include multiple perspectives into the model which allows for a better explanation of all kinds of disorders.
Cognitive neuroscience needs to be able to incorporate developmental and social/emotional influences into the paradigm in order to have a fully complete theory of psychopathology. Psychopathology traditionally means that there is a change in mood, thought, or behavior that impairs normal functioning (Pennington, 2002). The division that exists between developmental disorders and psychopathologies is misleading as they both fit into the description of psychopathology (Pennington, 2002). A cognitive neuroscience approach is aiming to explain many types of disorders, so adding emotion and social influences into the approach will be able to provide a more enriched model. This will also allow a more in-depth description of developmental disorders which would lead to better treatment.
Cognitive neuroscience also needs to focus more on individual difference. Often individuals with the same diagnosis will vary significantly with their symptoms (Pennington, 2002). As Dr. Kelley mentioned, often this means that they may have no overlapping similar symptoms at all, but have the same disorder. As we learned in lecture, is important to focus and understand the individual patients and their developmental disorder to fully be able to assess and provide effective treatment. For mental health practitioners, seeing children with these overlapping symptoms under the same disorder can make it hard to give them proper and unique treatment that best suits their individual profile (Pennington, 2002). The cognitive neuroscience approach does not capture the patients’ individual problems well enough to properly characterize, diagnose and treat them.
4. According to Burack et al, (2002), when and why should you use multiple control groups? (5 points)
According to Burack et al, (2002) matching control groups is very important when researching specific groups. It helps the researcher to answer the question of “normalcy” or “uniqueness” within an atypical population (Burack et al, 2002). The use of multiple groups being compared to the control group can provide a better strategy than a single matched group as it can allow for better precision when considering the level of functioning in the specific domain being looked at. For example, in lecture, we learned that comparing performance on a theory of mind task of autistic children to typically developing matched groups in expressive language, IQ, or age will lead to a better understanding than just compared to one matched group, say IQ.
The use of multiple control groups is beneficial when matching each typically developed group to the atypical group in question, such as children with autism (Burack. et. al, 2002). Multiple control groups can differentiate specific problems in functioning in more than one area (Burack. et. al, 2002). Having groups that are similar to the target group in certain domains can make it easier to identify differences or similarities in characteristics between the control groups and the target groups. This allows for a more precise focus on the specific domain in question and as well to better accurately match the level of functioning of the control group.
As we have learned in lecture, children with autism have a unique profile and often show ‘spikes’ in their performance so there can be issues when attempting to match groups (Burack. et. al, 2002). With the use of one comparison group to the target group, there are often differences in the level of functioning between groups. This is where multiple comparison groups are beneficial as they can account for some of the differences (Burack. et. al, 2002). Children with developmental language disorders (DLD) uniquely resemble children with autism in verbal abilities. Therefore, matching DLD children with autistic children on language ability would be a good match. As well, comparing children with autism to children with Fragile X syndrome in terms of social-communicative functioning is beneficial as they are similar in this domain (Burack. et. al, 2002). Both of these scenarios are good examples of when the target groups are properly matched on the level of functioning, the use of multiple control groups can be beneficial. It can highlight differentiation between groups but as well as help to better understand the domain of functioning of the target group. As they are matched on more groups that consider IQ, language, and age (for example), it allows for an increased understanding of their level of functioning of the specific domain in question.
There can also be downsides to doing research with multiple control groups. Often researchers match children on their mental age which often is not accurate in terms of chronological age. As Dr. Kelley mentioned, the same mental age but different chronological age means very different children. Children can have the same mental age but differ widely on a variety of factors that are under examination by the researcher. These differences are then not accounted for affecting the child’s task performance (Burack. et. al, 2002). This produces invalid and misleading results as the groups were not accurately matched.
- Burack, J. A., Iarocci, G., Bowler, D., & Mottron, L. (2002). Benefits and pitfalls in the merging of disciplines: The example of developmental psychopathology and the study of persons with autism. Development and Psychopathology, 14(02), 225-237. doi:10.1017/s095457940200202x
- Insel, T. R., & Cuthbert, B. N. (2009). Endophenotypes: Bridging Genomic Complexity and Disorder Heterogeneity. Biological Psychiatry, 66(11), 988-989. doi:10.1016/j.biopsych.2009.10.008
- Karmiloff-Smith, A. (1998). Development itself is the key to understanding developmental disorders. Trends in Cognitive Sciences, 2(10), 389-398. doi:10.1016/s1364-6613(98)01230-3
- Pennington, B. F. (2002). The development of psychopathology: Nature and nurture. New York: Guilford Press.