1
|
Levy R. The prefrontal cortex: from monkey to man. Brain 2024; 147:794-815. [PMID: 37972282 PMCID: PMC10907097 DOI: 10.1093/brain/awad389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 10/01/2023] [Accepted: 11/02/2023] [Indexed: 11/19/2023] Open
Abstract
The prefrontal cortex is so important to human beings that, if deprived of it, our behaviour is reduced to action-reactions and automatisms, with no ability to make deliberate decisions. Why does the prefrontal cortex hold such importance in humans? In answer, this review draws on the proximity between humans and other primates, which enables us, through comparative anatomical-functional analysis, to understand the cognitive functions we have in common and specify those that distinguish humans from their closest cousins. First, a focus on the lateral region of the prefrontal cortex illustrates the existence of a continuum between rhesus monkeys (the most studied primates in neuroscience) and humans for most of the major cognitive functions in which this region of the brain plays a central role. This continuum involves the presence of elementary mental operations in the rhesus monkey (e.g. working memory or response inhibition) that are constitutive of 'macro-functions' such as planning, problem-solving and even language production. Second, the human prefrontal cortex has developed dramatically compared to that of other primates. This increase seems to concern the most anterior part (the frontopolar cortex). In humans, the development of the most anterior prefrontal cortex is associated with three major and interrelated cognitive changes: (i) a greater working memory capacity, allowing for greater integration of past experiences and prospective futures; (ii) a greater capacity to link discontinuous or distant data, whether temporal or semantic; and (iii) a greater capacity for abstraction, allowing humans to classify knowledge in different ways, to engage in analogical reasoning or to acquire abstract values that give rise to our beliefs and morals. Together, these new skills enable us, among other things, to develop highly sophisticated social interactions based on language, enabling us to conceive beliefs and moral judgements and to conceptualize, create and extend our vision of our environment beyond what we can physically grasp. Finally, a model of the transition of prefrontal functions between humans and non-human primates concludes this review.
Collapse
Affiliation(s)
- Richard Levy
- AP–HP, Groupe Hospitalier Pitié-Salpêtrière, Department of Neurology, Sorbonne Université, Institute of Memory and Alzheimer’s Disease, 75013 Paris, France
- Sorbonne Université, INSERM U1127, CNRS 7225, Paris Brain Institute- ICM, 75013 Paris, France
| |
Collapse
|
2
|
Stip E, Javaid SF, Abdel Aziz K, Arnone D. Happy Birthday "One Flew Over the Cuckoo's Nest": A Momentous Tale in the Quest for an Effective and Ethical Approach to Psychosurgery. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 2023; 68:887-893. [PMID: 37424267 PMCID: PMC10657581 DOI: 10.1177/07067437231182658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
The anniversary of the publication of 'One Flew Over the Cuckoo's Nest' by Ken Kesey offers an opportunity for reflection on the use of neurosurgery in psychiatry. We used a narrative, historical and dialectical method to deliver an account of the controversial subject. A balanced representation of the negative and positive aspects, acknowledging some of the questionable ethical practices while describing well-reasoned applications is provided. It includes neurosurgeons, psychiatrists who have embraced these procedures with unwarranted enthusiasm and those who have opposed. Neurosurgical techniques for the treatment of severe mental disorders have evolved from rudimentary procedures which were used to 'correct' unwanted behaviours associated with a wide range of severe mental disorders to more refined and selective approaches used as a last resort to treat specific mental health conditions. In the absence of specific aetiological models to guide ablative surgical targets, non-ablative, stimulatory techniques have more recently been developed to allow reversibility when surgical treatment fails to obtain a sizeable improvement in quality of life. The subject is concretely illustrated by two eloquent clinical images: one on a series of brain computed tomography scans carried out on a Canadian population of subjects, who underwent leukotomy decades ago, and the other more contemporary on an implantation surgery to epidural stimulation. Alongside technical advances in psychosurgery, a regulatory framework has gradually developed to ensure vigilance in the appropriateness of patients' selection. Nevertheless, harmonisation of protocols around the world is necessary to ensure consistency in obtaining and maintaining the highest possible ethical standards for the benefit of patients. If the neurosciences promise today, in their new, better framed, and reversible applications, to provide answers to unmet therapeutic needs, we still must remain attentive to drifts linked the introduction of intrusive technologies for purposes of domination or behaviour modification that would impede our individual freedom.
Collapse
Affiliation(s)
- E. Stip
- Université de Montréal, Institut Universitaire en Santé Mentale de Montréal, Montréal, Canada
- Department of Psychiatry and Behaviour Science, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - S. F. Javaid
- Department of Psychiatry and Behaviour Science, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - K. Abdel Aziz
- Department of Psychiatry and Behaviour Science, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - D. Arnone
- Department of Psychiatry and Behaviour Science, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
- Centre for Affective Disorders, Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| |
Collapse
|
3
|
Wadhwa A. The History of Drug Development in Psychiatry: A Lesson in Serendipity. ADVANCES IN NEUROBIOLOGY 2023; 30:19-35. [PMID: 36928845 DOI: 10.1007/978-3-031-21054-9_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
The goal of this book is to provide a guide on modern day drug development in psychiatry. However, in order to understand current practices in drug development, it is important to first understand the history of psychiatry including early attempts at drug discovery and develoment. The early history of psychiatry is mired with the use of inhumane experimental treatments and the institutionalization of patients in asylums. Some of the earliest drugs used in these asylums were meant to sedate patients rather than treat underlying mental disorders. The earliest identified drugs treating mental disorders were born out of serendipitous discoveries which later led to their clinical effects being demonstrated through clinical trials and case studies. This is evident from the history of chlorpromazine, monoamine oxidase inhibitors, tricyclic antidepressants, lithium, and others. We discuss in detail about each of these psychotropic drugs, the events leading up to their discovery, and their role in formulating the biological basis of mental disorders including schizophrenia, depression, and bipolar disorder. Psychiatry, it seems has worked its way backwards from first identifying treatments before understanding the biological basis of mental disorders, in a sharp contrast to the other fields of medicine. With our growing understanding of the etiopathogenesis of mental disorders, drug development in psychiatry is evolving to develop treatments that target the underlying physiology of mental disorders.
Collapse
Affiliation(s)
- Abhishek Wadhwa
- University of Alabama at Birmingham, Department of Psychiatry and Behavioral Neurobiology, Birmingham, AL, USA.
| |
Collapse
|
4
|
Thill B. The fetal pain paradox. FRONTIERS IN PAIN RESEARCH 2023; 4:1128530. [PMID: 37025166 PMCID: PMC10072285 DOI: 10.3389/fpain.2023.1128530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 02/21/2023] [Indexed: 04/08/2023] Open
Abstract
Controversy exists as to when conscious pain perception in the fetus may begin. According to the hypothesis of cortical necessity, thalamocortical connections, which do not form until after 24-28 weeks gestation, are necessary for conscious pain perception. However, anesthesiologists and neonatologists treat age-matched neonates as both conscious and pain-capable due to observable and measurable behavioral, hormonal, and physiologic indicators of pain. In preterm infants, these multimodal indicators of pain are uncontroversial, and their presence, despite occurring prior to functional thalamocortical connections, has guided the use of analgesics in neonatology and fetal surgery for decades. However, some medical groups state that below 24 weeks gestation, there is no pain capacity. Thus, a paradox exists in the disparate acknowledgment of pain capability in overlapping patient populations. Brain networks vary by age. During the first and second trimesters, the cortical subplate, a unique structure that is present only during fetal and early neonatal development, forms the first cortical network. In the third trimester, the cortical plate assumes this function. According to the subplate modulation hypothesis, a network of connections to the subplate and subcortical structures is sufficient to facilitate conscious pain perception in the fetus and the preterm neonate prior to 24 weeks gestation. Therefore, similar to other fetal and neonatal systems that have a transitional phase (i.e., circulatory system), there is now strong evidence for transitional developmental phases of fetal and neonatal pain circuitry.
Collapse
|
5
|
Teixeira SA, Moreira JLDS, Sousa NRT, Pereira AMDC, Rodrigues PN, Santos ASD, Andrade AMLCD, Rolim Neto ML, Araújo JEB, Machado SSF, Vieira NB, Lima DGS, Filho FHP. Molecular basis and clinical perspectives of deep brain stimulation for major depressive disorder. J Cereb Blood Flow Metab 2022; 42:683-685. [PMID: 35048722 PMCID: PMC9051149 DOI: 10.1177/0271678x221074279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
It is possible to consider the stimulation of the cingulate gyrus in its portion below the corpus callosum (SCC, or subcallosal cingulate cortex) as an effective, promising, and safe alternative intervention for treatment-resistant depression. In studies with deep brain stimulation - DBS, when follow-on with functional magnetic resonance imaging and/or PET-CT (Positron emission tomography-computed tomography) is performed, it is observed an increase in the blood supply and glucose metabolism in this region, which is the anterior part of the limbic system. This same location has good experimental results also for the treatment of anorexia nervosa. The hypotheses suggest a greater activation of the reward system, a greater sense of well-being, and a consequent reduction in depressive symptoms, the objective of the treatment. Over the last 20 years, multicenter studies have shown symptomatic improvement in 50-60% of patients, and about a third even reach criteria for remission of the depressive disorder.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Modesto Leite Rolim Neto
- Juazeiro do Norte School of Medicine from Juazeiro do Norte - FMJ/Estacio, Juazeiro do Norte, Ceará, Brazil
| | | | | | - Nélio Barreto Vieira
- School of Medicine, Federal University of Cariri - UFCA, Barbalha, Ceará, Brazil
| | | | | |
Collapse
|
6
|
Abstract
Fetal pain perception has important implications for fetal surgery, as well as for abortion. Current neuroscientific evidence indicates the possibility of fetal pain perception during the first trimester (<14 weeks gestation). Evidence for this conclusion is based on the following findings: (1) the neural pathways for pain perception via the cortical subplate are present as early as 12 weeks gestation, and via the thalamus as early as 7–8 weeks gestation; (2) the cortex is not necessary for pain to be experienced; (3) consciousness is mediated by subcortical structures, such as the thalamus and brainstem, which begin to develop during the first trimester; (4) the neurochemicals in utero do not cause fetal unconsciousness; and (5) the use of fetal analgesia suppresses the hormonal, physiologic, and behavioral responses to pain, avoiding the potential for both short- and long-term sequelae. As the medical evidence has shifted in acknowledging fetal pain perception prior to viability, there has been a gradual change in the fetal pain debate, from disputing the existence of fetal pain to debating the significance of fetal pain. The presence of fetal pain creates tension in the practice of medicine with respect to beneficence and nonmaleficence.
Collapse
|
7
|
Norton ME, Cassidy A, Ralston SJ, Chatterjee D, Farmer D, Beasley AD, Dragoman M. Society for Maternal-Fetal Medicine Consult Series #59: The use of analgesia and anesthesia for maternal-fetal procedures. Am J Obstet Gynecol 2021; 225:B2-B8. [PMID: 34461076 DOI: 10.1016/j.ajog.2021.08.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Pain is a complex phenomenon that involves more than a simple physical response to external stimuli. In maternal-fetal surgical procedures, fetal analgesia is used primarily to blunt fetal autonomic responses and minimize fetal movement. The purpose of this Consult is to review the literature on what is known about the potential for fetal awareness of pain and to discuss the indications for and the risk-benefit calculus involved in the use of fetal anesthesia and analgesia. The recommendations by the Society for Maternal-Fetal Medicine are as follows: (1) we suggest that fetal paralytic agents be considered in the setting of intrauterine transfusion, if needed, for the purpose of decreasing fetal movement (GRADE 2C); (2) although the fetus is unable to experience pain at the gestational age when procedures are typically performed, we suggest that opioid analgesia should be administered to the fetus during invasive fetal surgical procedures to attenuate acute autonomic responses that may be deleterious, avoid long-term consequences of nociception and physiological stress on the fetus, and decrease fetal movement to enable the safe execution of procedures (GRADE 2C); and (3) due to maternal risk and a lack of evidence supporting benefit to the fetus, we recommend against the administration of fetal analgesia at the time of pregnancy termination (GRADE 1C).
Collapse
Affiliation(s)
- Mary E Norton
- Society for Maternal-Fetal Medicine, 409 12 St. SW, Washington, DC 20024, USA.
| | - Arianna Cassidy
- Society for Maternal-Fetal Medicine, 409 12 St. SW, Washington, DC 20024, USA.
| | - Steven J Ralston
- Society for Maternal-Fetal Medicine, 409 12 St. SW, Washington, DC 20024, USA.
| | - Debnath Chatterjee
- Society for Maternal-Fetal Medicine, 409 12 St. SW, Washington, DC 20024, USA.
| | - Diana Farmer
- Society for Maternal-Fetal Medicine, 409 12 St. SW, Washington, DC 20024, USA.
| | - Anitra D Beasley
- Society for Maternal-Fetal Medicine, 409 12 St. SW, Washington, DC 20024, USA.
| | - Monica Dragoman
- Society for Maternal-Fetal Medicine, 409 12 St. SW, Washington, DC 20024, USA.
| |
Collapse
|
8
|
Medicine SFMF, Planning SOF, Norton ME, Cassidy A, Ralston SJ, Chatterjee D, Farmer D, Beasley AD, Dragoman M. Society for Maternal-Fetal Medicine Consult Series #59: The use of analgesia and anesthesia for maternal-fetal procedures. Contraception 2021; 106:10-15. [PMID: 34740602 DOI: 10.1016/j.contraception.2021.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Pain is a complex phenomenon that involves more than a simple physical response to external stimuli. In maternal-fetal surgical procedures, fetal analgesia is used primarily to blunt fetal autonomic responses and minimize fetal movement. The purpose of this Consult is to review the literature on what is known about the potential for fetal awareness of pain and to discuss the indications for and the risk-benefit calculus involved in the use of fetal anesthesia and analgesia. The recommendations by the Society for Maternal-Fetal Medicine are as follows: (1) we suggest that fetal paralytic agents be considered in the setting of intrauterine transfusion, if needed, for the purpose of decreasing fetal movement (GRADE 2C); (2) although the fetus is unable to experience pain at the gestational age when procedures are typically performed, we suggest that opioid analgesia should be administered to the fetus during invasive fetal surgical procedures to attenuate acute autonomic responses that may be deleterious, avoid long-term consequences of nociception and physiological stress on the fetus, and decrease fetal movement to enable the safe execution of procedures (GRADE 2C); and (3) due to maternal risk and a lack of evidence supporting benefit to the fetus, we recommend against the administration of fetal analgesia at the time of pregnancy termination (GRADE 1C).
Collapse
Affiliation(s)
| | | | - Mary E Norton
- The Society for Maternal-Fetal Medicine: Publications Committee.
| | - Arianna Cassidy
- The Society for Maternal-Fetal Medicine: Publications Committee.
| | - Steven J Ralston
- The Society for Maternal-Fetal Medicine: Publications Committee.
| | | | - Diana Farmer
- The Society for Maternal-Fetal Medicine: Publications Committee.
| | - Anitra D Beasley
- The Society for Maternal-Fetal Medicine: Publications Committee.
| | - Monica Dragoman
- The Society for Maternal-Fetal Medicine: Publications Committee.
| |
Collapse
|