EDITORIAL NEUROPLASTICITY, DEVELOPMENTAL AND PSYCHOTHERAPY RESEARCH IN THE LAST DECADES

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1 EDITORIAL NEUROPLASTICITY, DEVELOPMENTAL AND PSYCHOTHERAPY RESEARCH IN THE LAST DECADES OLTEA JOJA 1 Titu Maiorescu University, Bucharest Institute of Endocrinology C.I. Parhon, Bucharest Abstract This article is showing the last decades research data concerning psychotherapy and its relevance for the phenomenon of neuroplasticity. The aim of this paper is to contribute to the understanding of how external influences, including psychotherapy, may induce changes at the neurobiological level. The study is addressing psychologists and psychotherapists of any direction as well as young researchers. Keywords: Neuroplasticity, Cognitive Behavioural Psychotherapy, Developmental, Reappraisal 1. INTRODUCTION Eric Kandel, who was awarded the Nobel Prize in physiology and medicine in 2000, used to open his lectures with the following rather surprising statement: After leaving this lecture your brain and its synapses will not be the same as before. The mechanism to which Kandel makes reference relies on the amazing ability of the human brain called neuroplasticity, brain plasticity ( cortical remapping ), i.e. the brain s ability to dynamically reorganize itself, by changing - in the process - the neural circuits at cell or molecular level. More specifically, the neurons, as well as the neural networks, can actually change their connections and behaviour, as a response to new information, to sensory stimulation, during the development process or in the case of injuries or dysfunctions. Traditionally, the brain s development was thought to stop after the first years of life, while the connections established between neurons in early childhood were to remain unchanged for the rest of one s life. Until recently, neuroplasticity was 1 Correspondence: Dr. Oltea Joja, C.I.Parhon Institute of Endocrinology Blvd. Aviatorilor Bucharest Romania; oltea_joja@yahoo.com; Tel: ; Fax:

2 thought to be primarily a capacity of the child s brain, at this level labelled as developmental neuroplasticity. Also neuroplasticity was found to occur throughout the entire life, compensating the loss of brain functions. Due to this ability, the brain may adapt its activity in response to new situations or environmental changes. We know that neuroplasticity occurs (1) early in life, when the immature brain (self)organizes - the so-called developmental neuroplasticity; and (2) following brain injuries, to compensate for the lost functions or to increase the effectiveness of the remaining functions. Also, nowadays supported by empirical evidence provided by neuroimaging is the fact that throughout adulthood, every time we are learning something new and store the new information in our memory, the brain changes its physiological and anatomical configuration. Data show that any new experience may leave traces; it can either strengthen or weaken the existing synaptic connections. Also, a new experience can create new neural networks or it may change the existing ones of the cerebral cortex or of the emotions regulating structures (subcortical structures). This last aspect provides a specific explanation for stress patterns in general and for «interpersonal stress» in particular, such as the significant changes that may occur in children experiencing maternal deprivation. 2. A BRIEF HISTORY OF NEUROPLASTICITY The idea of neuroplasticity was introduced in 1890 by William James in The Principles of Psychology (James, 1890), and was then ignored for quite a while. The Polish neuroscientist Jerzy Konorski is known to be the one who coined the term neuroplasticity, suggesting in a study published in 1948 (Hebb, 1949) that brain neurons, which coincidentally were activated in time due to their proximity, caused the potential connections to be transformed into actual excitatory connections. This idea that synapses strengthen with their use was further sustained by the Canadian psychologist Donald Olding Hebb ( ). He is considered as being the father of neuropsychology, due to his extensive studies concerning the differentiated functioning of neural networks in the learning processes. Hebb s seminal study, The Organization of Behaviour (Hebb, 1949), emerged from the observations in brain surgery, which he correlated to his research on human behaviour. He described the psychological processes as biological functions of the brain, which also enable that higher function of the mind. Hebb combined data about the brain s activity and behaviour into a single theory relating to body and mind. His approach integrated his foregoers observations, as those of Pavlov, Watson, Thorndike, and Skinner. The Hebbian statement Neurons that fire together wire together (Hebb, 1949) indicated that repeating the same cognitive pathway will strengthen the underlying synaptic connection(s) and that the change in a synapse s strength depends on the pre- and post-synaptic neural activity. 4

3 A series of neuroimaging observations on brain activity along the last decades questioned the localization theory, which stated a specialization of different areas for different functions of the brain. This theory of modularity, stemming from the old phrenology, stated that the brain is organized in modules, which display specific functions, i.e. brain areas are domain specific for different cognitive processes (Caramazza & Coltheart, 2006) Recovery after brain injuries and function compensation are no more an exception, but indicate that brain areas are interconnected, processing information in a distributed manner. Hence the second major brain theory, the theory of distributive processing, postulating that the brain is interactive and that brain regions are functionally interconnected and not merely specialized. Based on neuroimaging methods, Macintosh, a Toronto researcher, indicated that modularity is mainly observed inside the sensory and motor systems. Beyond these specialized receptors, modularity becomes fuzzier and the cross connections between systems increase (Mcintosh, 1999). Macintosh focused his research upon memory and learning processes, which appear to be ubiquitous properties of the brain, as physiological data have consistently shown that almost all parts of the nervous system show the capacity for learning and memory (Mcintosh, 1999, p541). The complex registered interactions between brain regions are not as contradicting as it may seem to the former data concerning brain injuries and functional localization. As Macintosh put it: the idea of emergent properties from neural interactions is neutral with respect to the lesion findings. Lesion findings give clues about functional organisation, but are silent as to how the function is carried out (Mcintosh, 1999, p543). These new differentiated views construed upon empirical data are bridgeing the two major theories on brain activity. The theory of modularity and the theory of distributed processes may be viewed in an integrative way as: a region can play a different role in many functions and that role is governed by its interactions with anatomically related regions (Mcintosh, 1999, p543), meaning a paradigm shift. 3. NEUROPLASTICITY RELATED TO DEVELOPMENTAL DATA We will hereto refer to the observations included by the research team around Eric Kandel in their broad analysis of data published as a special article in 2005 (Etkin et al., 2005). Etkin et al. indicate three developmental factors favouring the occurrence of a psychiatric disorder: 1) vulnerability genes for anxiety and mood disorders; 2) temperament and the innate emotional reactivity biases; and 3) histories of abuse or trauma. The authors resorted to Jerome Kagan (Kagan et al., 1987), a key pioneer of developmental psychology, who made extensive research upon the infant s temperament, defining two types of temperament. He identified 5

4 infants exhibiting temperamental shyness and inhibition, and found that these traits are (in)heritable (Emde et al., 1987) and relatively stable into young adulthood (Schwartz et al., 1987). This inhibited type of temperament can be assessed during the first year of life by the level of behavioural inhibition and the autonomic and hypothalamic-pituitary-adrenal hyper-reactivity to novelty. Later on, these children will be at risk of developing social anxiety (social phobia) during childhood or adolescence and generalized anxiety disorder as adults. Kagan identified the second type, the uninhibited temperament in children, who are open to new people and situations, showing a sociable, outgoing behaviour and a more pronounced emotional and behavioural reactivity. Adolescents who displayed this kind of reactivity during childhood are at risk of developing impulsive, aggressive, antisocial behaviours and even bipolar disorder (Hirshfeld- Becker et al., 1987). A common and disabling consequence of the first type described, the inhibited temperament, is social anxiety (Biederman et al., 2001), also called social phobia, ranking third among psychiatric disorders (Pollack, 2001), with a lifetime prevalence of 3-13% (APA, 2000). Data are indicating that shyness and behavioural inhibition in toddlers correspond to the developmentally early phenotype, with a set of vulnerability genes favouring the development of social anxiety (Etkin et al., 2005). Such individuals process information in a particular manner, in the sense of an excess of bottom-up approach, as opposed to the topdown approach, in response to threats or stressors (Kagan et al., 1987). These information processing strategies are associated with a certain cognitive style, as well as with a certain teaching style. The top-down approach often refers to analysis or what we call in a more modern term decomposition, while the bottom-up approach goes the opposite way and means synthesis or recomposition of a system by piecing together sub-systems. In the bottom-up approach basic elements are specified in greater detail. This approach is also called the small chunk, suggesting that we expect or perceive elements, starting with the smaller, finer details of that element, and build our way up until we obtain a solid representation of it in our mind. We find such an approach in people who understand concepts and ideas starting from details, and then build their way up, to the essence of a more general concept. 4. NEUROBIOLOGICAL INFLUENCES OF PSYCHOTHERAPY As referred to above, the parenting style is relevant to a child s development, stimulating or inhibiting reactive patterns. According to a set of data of Rubin et al. (Rubin et al., 2002), behavioural inhibition in toddlerhood may predict reticence with unfamiliar peers at four years of age only if the toddlers mothers were intrusive and made derisive comments. If mothers were neither intrusive nor derisive then their children s inhibition in toddlerhood was not significantly 6

5 associated with peer reticence at four years. Such data suggest that social anxiety may be significantly influenced by parental behaviour and attachment styles, and therefore implications for therapy and potential preventive measures in relation to the development of social anxiety have to be considered. Family psychotherapy programs and toddler-parent psychotherapy have been developed for fostering secure attachment relationships in young children, as described by recent research (Sexson et al., 2001). Cognitive-behaviour therapy (CBT) in adults and children showed efficacy in helping anxious people to disengage their attention from threatening stimuli.(fox et al., 2002) (Derryberry & Reed, 2002). Reviewing data, Etkin et al. suggested that structured learning, that occurs in CBT and in other similar approaches, may supplement the type of learning, which normally occurs in the context of a secure mother-child attachment or within an adaptive parenting style (Etkin et al., 2005). The systematic, structured cognitive-behavioural approach appears to impact behavioural inhibition in a way, which is alike to the regulating influence of maternal behaviour towards the child s inhibition. Hence the question: under which condition might these effects occur and how extensively might CBT or another type of psychotherapy compensate attachment deficits? This question still represents research in progress. Extensive studies will be necessary for responding to this question. The observations concerning comparable effects of maternal behaviour and attachment upon the child s reactivity appear as adding arguments for the influences of psychotherapy on the brain. The data presented above are in accordance with the observation that psychological constructs relevant to several modalities of psychotherapy have demonstrable neurobiological correlates, as indicated by functional neuroimaging studies in healthy subjects (Roffman et al., 2005). Roffman et al. (2005) reviewed fourteen functional neuroimaging investigations for examining the measuring results of the psychotherapy effects on brain function in patients with anxiety or depression. Behaviour therapy in anxiety disorders was consistently associated with the attenuation of brain-imaging abnormalities in regions involved in the pathophysiology of anxiety and with the activation of brain regions specifically related to positive reappraisal of anxiogenic stimuli. Thereby reappraisal appears to be one of the bridges between psychotherapy and its neurobiological effects. Reappraisal, also called cognitive reappraisal, is the reinterpretation or reassessment of stimuli or thoughts. In cognitive therapy, reappraisal is a commonly used emotion regulation technique accomplished through the reinterpretation of the meaning of a stimuli or a situation. The technique is usually used to down-regulate negative emotions such as threat, anxiety, and frustration, whereby patients register and evaluate their negative thoughts and learn to replace them with more positive thoughts. Reappraisal is at the same time a coping mechanism in stress management, when an individual tries to rephrase his negative 7

6 thoughts in a positive manner, or at least in a softer, and less sententious manner. The ability to use reappraisal, called cognitive reappraisal ability (CRA) has been comparatively assessed and appears as being an important moderator of the link between stress and depressive symptoms (Allison et al., 2010). Reappraisal is an early intervention in the coping process, as it occurs in the first development stage of an emotion, and is therefore an antecedent-focused strategy, while the suppression of negative emotions, which is the favourite theme of psychoanalysis, is a response-focused type strategy (the late development stage of an emotion) that attempts to ignore the emotion. (Gross, 2002) Gross suggested a significant difference between emotion regulation strategies occurring in the early stages, such as reappraisal, with a different outcome profile, and strategies occurring in a later stage, such as suppression. Thus, reappraisal, as an emotion down-regulating strategy, causes changes in the structure of a situation (restructuring), so that the emotional impact is lowered, while suppression inhibits the external display of inner feelings. In an article from 2002, the same author, Gross (Gross, 2002) noted on some relevant aspects concerning the comparison between reappraisal and suppression, which we resume: (1) reappraisal reduces both the negative emotion experience and its expression, and enhances the positive emotion experience and expression, while the suppression also reduces the behavioural expression but fails to reduce the negative emotion experience; (2) reappraisal does not affect memory, while suppression may consume the individual s cognitive resources, impairing the information memorized during the emotion regulation; (3) physiologically, reappraisal is not associated with an increased sympathetic activation, as does suppression and moreover, suppression may result in higher blood pressure in social partners; (4) when considering the individual s social functioning, when supressing individuals share less of their positive and negative emotions, which may lead to weakening the social support and being less liked by the others, consequences which are not present in the context of the reappraisal process. 5. DISCUSSION Neuroplasticity is considered to be one of the most important phenomena described at the end of the twentieth century. Data of the last decades have been changing our view both of psychopathology and psychotherapy. These new insights brought about by the neuroimaging techniques lead to a new understanding of the brain s activity, integrating the two main theories, that of modularity and that of distributed processes. We know now that just alike to the influence of environmental factors, and similar to any learning process, psychotherapy may trigger changes in the neurochemistry of the brain. The structured cognitive-behavioural approach may 8

7 impact the behavioural inhibition in a way, which is alike to the regulating influence of maternal behaviour towards the child s inhibition. We have been noting the above aspects, which are less known to young psychotherapists, in order to emphasize the neurobiological dimension of psychotherapy and the effectiveness of the demonstrated CBT approaches. Data reviewed in this study argue for the need to further consider counselling and psychotherapeutic approaches by means of a sound knowledge of their neurobiological basis. Such a view will be more relevant for our responsibility towards clients and patients. REFERENCES Allison S. Troy, Frank H. Wilhelm, Amanda J. Shallcross, and Iris B. Mauss Seeing the Silver Lining: Cognitive Reappraisal Ability Moderates the Relationship Between Stress and Depressive Symptoms. Emotion. Author manuscript; available in PMC 2012 February 13. Published in final edited form as: Emotion December; 10(6): APA: Diagnostic and statistical manual of mental disorders DSM-IV-TR. Washington, DC, American Psychiatric Press, Inc., Biederman J, Hirshfeld-Becker DR, Rosenbaum JF, et al: Further evidence of association between behavioral inhibition and social anxiety in children. Am J Psychiatry 2001; 158(10): Caramazza, A., Coltheart, M. Cognitive Neuropsychology twenty years on. Cognitive Neuropsychology.Psychology Press. 23(1),3 12. (2006). Derryberry D, Reed MA: Anxiety-related attentional biases and their regulation by attentional control. J Abnorm Psychol 2002; 111(2): / cited by Etkin et al. (2005)) Emde RN, Plomin R, Robinson JA, et al: Temperament, emotion, and cognition at fourteen months: the MacArthur Longitudinal Twin Study. Child Dev 1992; 63(6): , cited by Kagan et al., Etkin A, Pittenger C, Polan HJ, Kandel ER Toward a Neurobiology of Psychotherapy: Basic Science and Clinical Applications J Neuropsychiatry Clin Neurosci Spring; 17(2): Review. Fox E, Russo R, Dutton K: Attentional bias for threat: evidence for delayed disengagement from emotional faces. Cogn emot 2002; 16(3): (cited by Etkin et al., 2005). Gross J.J. Emotion regulation: Affective, cognitive, and social consequences. Psychophysiology, 39 ~2002!, Cambridge University Press. Printed in the USA. 9

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