Neuropsychiatry

The Neuropsychiatry of Limbic and Subcortical Disorders

The Neuropsychiatry of Limbic and Subcortical Disorders

Salloway S, Malloy P, Cummings JL, editors

Washington (DC): American Psychiatric Press; 1997. 217 pp with index

ISBN 0-88048-942-1 (cloth)

The limbic system is a topic of considerable interest to both psychiatrists and neurologists. For biologically oriented clinicians, one can barely go a week without encountering some reference to a limbic disorder. The explosion of information about the interconnectedness of various brain regions is forcing both practising clinicians and neuroscientists to grapple with all brain regions, not just a favorite few. Inevitably, one is confronted with the need to understand the function of the limbic system. The definition of the limbic system has steadily broadened over time to include not just the medial circuit of Papez, but structures that are functionally associated with it. In common usage then, the term “limbic system” speaks to a set of cognitive functions; these functions are subserved by a network of cortical and subcortical structures.

In this spirit, The Neuropsychiatry of Limbic and Subcortical Disorders represents a snapshot of the state of knowledge of the limbic system. This book expands on the summer 1997 special issue of The journal of Neuropsychiatry and Clinical Neurosciences on the same topic. Published by the American Psychiatric Press, it is a high-quality book at a reasonable price, with many colour figures and photomicrographs.

This book is not an easy introduction to the anatomy and function of the limbic system. As the editors state in their introduction, “The essays in the volume cover a broad range of basic and clinical material at various levels of difficulty. … Some of the chapters present complex material requiring careful study and perhaps a second reading.” This is not an understatement. The book is divided into 2 sections: Anatomy and Neurochemistry, and Clinical Syndromes. It is the first, more technical section that presents the most difficult material. For neuroscientists familiar with the terminology, these chapters represent an excellent resource. They are good summaries of the anatomical literature with extensive references. Most chapters have 50 to 100 well-selected references, though a few contain up to 300. There is an abundance of photomicrographs, many of which have been previously published and retain an alphabet soup of anatomical abbreviations. This may present a problem, primarily to the student of behaviour wanting to learn more about the neural substrates.

If the anatomy section suffers from over-inclusion of information, then the clinical section suffers from a lack of rigour, and must be taken as hypothetical in many cases. There are interesting ideas here, and the authors have put forth several theories regarding the pathology of syndromes including temporal lobe epilepsy, emotional experience, recovered memory and religious experience.

While many of the chapters focus purely on the anatomical or clinical aspects of the limbic system, a few successfully link anatomy and function. The chapter entitled “Neurobiology of Fear Responses,” by Michael Davis, is a particularly cogent exposition of the role of the amygdala in fear. This chapter, appropriately positioned between the 2 major sections, introduces concepts such as classical conditioning, and outlines the evidence from lesion and excitation studies for the amgydala’s function. It is accessible to both anatomists and behaviourists. The chapter entitled “The Neurobiology of Emotional Experience,” by Kenneth Heilman, lucidly outlines several theories of emotion, ultimately arriving at the modular theory. One version of the modular theory states that emotions are mediated by anatomically distributed modular networks, and it is the relative activation of these modules that gives rise to the variety of human emotion. The location of the modules, of course, overlaps with the limbic system. The chapter entitled “Limbic-Cortical Dysregulation,” by Helen Mayberg, is an excellent exposition of a theory of the functional organization of medial cortical and limbic structures. This theory, based largely on human functional imaging (positron emission tomography and functional magnetic resonance imaging), is quite successful in unifying often contradictory studies regarding cingulate function. Finally, the chapter by Koob and Nestler entitled “The Neurobiology of Drug Addiction” is a good summary of the neural substrates that underlie reward behaviour, and how drugs of abuse affect them.

All of the authors in this book have published extensively in their fields. Consequently, most of the material has appeared in other review articles. Nevertheless, it is convenient to have the information all in one place, together with the colour reproductions.

In a book that juxtaposes both anatomical and syndromic chapters, it becomes painfully obvious that our knowledge of brain wiring is fast outpacing our ability to describe behaviour. A great deal is known about connectivity, neurotransmitters and gene expression, but how can these be related to only a crude description of human experience? Saver and Rabin, in their chapter on religious experience, offer several convincing descriptions that would suggest that the mystical quality of a religious experience is a manifestation of limbic activity, if not outright seizure activity. While quite reductionist, it may even be true, but something is lost in the characterization of the experience. It is no coincidence that virtually every work of fiction is fundamentally concerned with “limbic function.” The conclusions of all classical tragedies are known — it is the human experience that captures our interest. When speaking about the function of the limbic system, one quickly realizes that the putative functions, emotion, memory and motivation, are difficult to describe, let alone quantify — hence, an unlimited supply of literature. Unlike other cognitive functions such as perception, language and motor behaviour, these limbic processes do not lend themselves easily to experimentation.

Are these processes unquantifiable? Perhaps the language is wrong. For example, anxiety is an emotion variously localized to the limbic system. One can go to great lengths using different rating scales to quantify the severity of anxiety, but ultimately one relies upon individual interpretation of crude descriptions. What if an emotion like anxiety were compacted to a measure of probability? For example, “I feel like I’m going to die,” represents the assignment of a non-zero probability to the outcome of death. While the individual may know death is unlikely, it nevertheless creates a situation of uncertainty: “I know I won’t die, but then again, what if I do?” Measures of uncertainty, while not in the usual parlance of emotion, do lend themselves to quantification, and ultimately correlation with neural activity. Perhaps it is time for a shift in the description of limbic behaviour. Only when these phenomena are accurately described will we be able to relate them to brain function and dysfunction.

Dreaming and Other Involuntary Mentation

Dreaming and Other Involuntary Mentation: An Essay in Neuropsychiatry

Arthur W. Epstein. Madison (CT): International University Press; 1995

The author of this essay, Dr. Arthur Epstein, is emeritus professor of psychiatry and neurology at Tulane University of Louisiana in New Orleans, and director of the Tulane Psychoanalytic Program since 1977; he is also a past president of the Society of Biological Psychiatry and of the American Academy of Psychoanalysis. He has a major interest in neuropsychiatry and has paid attention in his research and practice to the biological basis, as well as the psychodynamic meaning, of dreaming and other involuntary (unconscious) mentation.

In this interesting short book, written in a sharp, direct, minimalistic literary style, he presents with great simplicity, clarity and brevity many complex, fundamental aspects of the brain and mind, and particularly the associative areas of the brain.

He makes the fundamental point that the mind works in “connectivity” — the sets of neuronal and dendritic connections permitting the associative areas of the brain to function and to act as the organic substratum for the many brain functions, including involuntary mentation such as dreaming. He elaborates on this point in sections on associative processes, showing their normal as well as pathological patterns, with clinical and laboratory examples from nominal aphasia and epileptic states, in which neuronal excessive discharge during dreaming presents the involuntary (i.e., unconscious, that could in part become conscious) mentation in the recurrent dream-epilepsy equivalence. Here again, he uses both laboratory and clinical examples of all-night sleep studies. He deals with many aspects of sleeping and dreaming, including REM sleep behaviour disorders, impaired modulation and narcolepsy. He goes on to consider dominant networks that produce imperative fetishistic and phobic ideas. In one chapter he deals with dominant networks in relation to the imperative ideas of obsessive-compulsive disorders, and in another he concentrates on the origin and transmission of imperative ideas. He ends with his thoughts on implications for psychodynamic science.

I enjoyed reading this book. Its content is very clearly and simply presented. In fact, by presenting in an interesting and instructive way complex phenomena that bridge brain, mind and several neuroscientific disciplines (neurology, psychodynamic psychiatry, and many aspects of neuroscience, including sleep research), with clinical and research examples, he has accomplished a major tour de force. This is a useful and instructive book for all who are involved in our disciplines. I thoroughly recommend it.

Psychiatry in Progress

Psychiatry in Progress, Volume 3: Neuropsychiatry in Old Age

C Stefanis, H Hippius, editors

Toronto: Hogrefe &Huber; 1996. 171 p

This slim volume contains the proceedings of a symposium sponsored by Ciba-Geigy and held on the island of Rhodes, Greece, in April 1994. Its aims are both to outline the current state of scientific knowledge on the biology of aging and to address major issues relating to neuropsychiatric disorders in the elderly. Unlike the published proceedings of many other symposia, this volume is well written, well edited, and flawlessly produced.

Internationally recognized experts, most from Europe, distill knowledge on selected topics that range from molecular biology to ethical issues near the end of life. For example, Wisniewski writes on the neuropathology of Alzheimer’s disease caused by fibrillation of A, p, and tau proteins; Copeland writes on the comparative epidemiology of dementia and depression in old age; Ritchie writes on psychological testing, and Gottfries writes on the pharmacotherapy of cognitive deficits. Each chapter begins with a useful summary and finishes with pertinent references and discussion from the floor.

The chapters are concise and informative but not comprehensive. Usually, each chapter presents a point of view or develops a theme that summarizes current knowledge and highlights a topic or issue requiring further research. For example, Bar and Gispen cite evidence that neuroplasticity exists throughout the life span and may be modifiable with calcium channel-blocking drugs; Muller-Spahn and Hock examine the spectrum of dementia and depression and propose biological approaches to the differential diagnosis of these disorders.

Obviously, this book is neither a text of neuropsychiatry in old age nor a reference work. Rather, it contains a series of interesting and authoritative reports on 13 selected topics. It is therefore a valuable book for the geriatric psychiatrist or psychologist who wants some challenging recreational reading or even for the general psychiatrist who wants to explore more recent developments in the neuropsychiatry of old age.

Clinical Child Neuropsychiatry

Clinical Child Neuropsychiatry

C Gillberg

New York: Cambridge University Press; 1995. 368 p

This reviewer was privileged to hear a remarkable presentation by Dr Christopher Gillberg, a Swedish child psychiatrist, in Australia in 1992. He was one of the invited plenary speakers at the International Association for the Scientific Study of Mental Deficiency at the Gold Coast Conference in 1992. He spoke clearly and precisely as he related a wealth of personal research about the underlying medical conditions leading to the autistic disorders. During the past 10 years, Dr Gillberg has become a preeminent world authority in the field of mental retardation and psychiatric disorder. This textbook confirms that his writing matches his memorable presentation in Australia. It is an encyclopedic distillation of not only the psychiatric aspects of mental retardation but also the organic factors involved in obsessional disorders, attentional disorders, language disorders, sleep and elimination disorders, and more. Even more surprising is his compilation of the existing knowledge on behavioral and physical phenotypes, which he correlates with genetic findings, a task not previously attempted to this reviewer’s knowledge.

With Gillberg’s inclusion of the psychiatric sequelae of traumatic brain injury in children, epilepsy, cerebral palsy, and brain tumors, along with their neurodevelopmental, neuropsychological, and laboratory workups, directors of child and adolescent psychiatry education, after reading this textbook, will likely have to insist on the inclusion of 6 months to a year of developmental pediatric and pediatric neurology in child psychiatry training in order to allow themselves to be called “Complete Child Psychiatrists”!

Although the Ontario Health Study indicates that the percentage prevalence of emotional and behavioral disorders in children and adolescents is in the double figures, Gillberg, in his chapter on epidemiology, states that up to 10% of children have neuropsychiatric disorders(the bulk of which manifest as attention deficit disorders). The importance of workup and diagnosis by trained clinical child psychiatrists is emphasized by such figures.

In this textbook, we are brought up to date with molecular genetics in diagnosing such conditions as fragile X syndrome, Prader-Willi syndrome, Angelman’s syndrome, neuroflbromatoses, Duchenne muscular dystrophy, and possibly Williams syndrome. Other background factors, such as temperament, prenatal, sociocultural, and familial factors are noted, and an excellent bibliography is provided for more detailed reviews.

A brief but significant chapter on normal development includes not only a practical table of milestones (useful for clinical inventory) but also a clear exposition of Baron-Cohen’s “Theory of Mind” and subsequent development of complex social interaction and empathy.

As would be expected from one of Gillberg’s primary areas of interest, the chapter on autism and “autism spectrum” disorders is excellent. It not only brings us up to date with DSM-IV definitions, but also it supports Lorna Wing’s thesis that there is doubtful specificity of “pure” Kanner autism. Instead, Gillberg proposes that there are a number of conditions that result in disorders of “empathy.” He makes a compelling argument against the current classification of pervasive developmental disorders. This is particularly supported when he lists 17 organic conditions that have been confirmed as producing the autism spectrum. The standardized neuropsychiatric assessment and relevant laboratory workups to detect these 17 conditions are outlined. Of particular importance and interest to child psychiatrists is his detailed review of the current state of knowledge of Asperger’s syndrome, including an outline of the controversy over classification and the long-term outcome for those suffering from this condition.

There is a surprising inclusion of anorexia nervosa in the chapter, which also links obsessive-compulsive disorders with tic disorders and Tourette’s syndrome. He outlines the hypothesis that anorexia nervosa is a final common pathway disorder including psychosocial, neurochemical, and local gastric factors with a minimal relationship to family dysfunction.

Gillberg makes a significant contribution to clinical diagnosis and treatment as well as future research potential by introducing the term “DAMP” disorders. This new umbrella term covering “Deficits in Attention, Motor Control and Perception” is much clearer than the alternative phrase, “Minimal Brain Dysfunction.” It was coined by Gillberg in 1983 and is now accepted by the Nordic consortium of child psychiatry. Given that attentional disorders, motor control disorders, hyperkinetic disorders, perceptual (reading and writing) disorders, and speech and language disorders overlap, this is a much-needed classification that is worthy of considerable scrutiny by the American Psychiatric Association and World Health Organization.

Another new term for this reviewer is “Jactatio capitis.” No, it is not a new paraphilia, but it has implications for those clinicians working with tic disorders and other repetitive rhythmic disorders. (To find out more, the reader is referred to Chapter 9.)

The longest chapter (70 pages) and the one filled with the most “meat” is entitled “Specific Syndromes Not Otherwise Referred To.” Here, Gillberg is at his most-knowledgeable best, compiling the prevalence, sex ratios, behavioral phenotypes, pathogenesis, diagnosis, workup, treatment, and outcome of congenital developmental syndromes. My only criticism of this chapter, and it is rather muted, is that the chapter could have included more pictures of the dysmorphic features of some of the syndromes. I suppose, however, that the knowledgeable reader should have a companion volume such as the Nyhan and Sakatis textbook, Diagnostic Recognition of Genetic Disease, on the shelf.

The psychopharmacology of child neuropsychiatric syndromes is complete, succinct, and up to date and draws heavily on the author’s former working relationship with Magda Campbell.

For his next edition (hopefully because of the importance of this textbook there will be many future editions), this reviewer would like to see expansion in the size of the specific syndrome chapter as well as an expansion on the psychiatric sequelae of and psychosocial intervention with traumatic brain injury, cerebral palsy, and epilepsy.

The textbook gains tremendous consistency from its single authorship. It is a major textbook, more comprehensive, detailed, and current than any other on developmental psychiatry. It, along with Levine and others’ 1983 textbook, Developmental-Behavioural Pediatrics, should be on the shelf of every child psychiatry resident, notwithstanding its price. It has fulfilled Gillberg’s goal of being “the first such compilation on clinical child neuropsychiatry, in which all the infancy, childhood or adolescent onset disorders in which mental, emotional and behavioural problems predominate . . . and for which biological factors . . . play a major . . . role are included.” Congratulations, Dr Gillberg!

Career Planning for Psychiatrists

Career Planning for Psychiatrists

KM Mogul and LJ Dickstein, editors

Washington DC: American Psychiatric Press, Inc; 1995. 286 p

This book is meant to be a “menu of career possibilities,” and nearly 30 American psychiatrists, either individually or in pairs, have written chapters describing their particular type of psychiatric practice. These chapters are then grouped into sections based on: 1) practice setting (hospital, outpatient, organized care, and academic settings); 2) speciality (child, geriatric, forensic, addiction); 3) specific treatment modality (psychoanalysis, family therapy, group therapy); 4) research; and 5) administration.

Although there is no consistent format, most chapters provide an overview of the history and development of particular areas of psychiatry, followed by a description of what each practice entails, the training required, candid assessments of rewards and frustrations, as well as ethical, economic, and legal issues, and anticipated opportunities. Within each chapter, references are also made to professional organizations that can be contacted for further information such as a listing of fellowships.

The book does succeed in capturing the current diversity of psychiatric practice in the United States of America (USA). Being aware of the possibilities is probably an important preliminary step when contemplating a career. However, the book could have been inspiring had it included more personal stories about how a contributor’s career actually evolved.

This format was used in JM Morihisa’s chapter: “Zen and the Art of Biological Psychiatry Research.” This wonderfully subjective account describes the exact training undertaken as well as the personal philosophy of this successful researcher. It also highlights the importance of mentors in the process of career development.

Unfortunately, there are no other personal vignettes that would have further demystified how careers evolve. I believe such an approach would have provided needed optimism for trainees who are acutely aware of the massive changes that will occur and are occurring in mental and other health services. The present climate of change is sometimes so overwhelming that it can lead trainees to become sceptical about whether it is even possible to choose from the current “menu” of career options. I think further personal accounts would have provided a more accurate picture of the innovation, flexibility, and unpredictability that have often been involved in creating careers in psychiatry. This ability to innovate was alluded to in the chapter on occupational psychiatry (”Psychiatry in Industry”), and a subjective account of this would have been enlightening.

Despite these limitations, this compilation is fairly informative and often makes explicit those aspects of practice that add to or detract from our enjoyment of the work. While the scope is quite broad, it is not comprehensive, and there are notable lacunae such as neuropsychiatry (I refer interested readers to the Journal of Neuropsychiatry vol 6, no 1, p 96-101, for 6 personal accounts by leaders in the field of neuropsychiatry of the training paths they took and why) and practice in rural areas. Nevertheless, this book should appeal to medical students and psychiatric residents, especially those in smaller programs where lack of role models in subspeciality areas can be a problem. The most successful aspect of the book, however, is unintentional: it provides an interesting window into the scope and structure of psychiatric practice in the USA at the very moment when massive changes have begun. It allows psychiatrists outside the USA the chance to compare and reflect on the similarities and differences of various models of psychiatric practice, with some possible insights into how psychiatric practice itself is influenced by the system in which it is embedded.

The Schedules for Clinical Assessment in Neuropsychiatry

The Schedules for Clinical Assessment in Neuropsychiatry. Version 2

Wing JK, chief editor

Geneva: World Health Organization—Division of Mental Health; 1994.331 p.

The Schedules for Clinical Assessment in Neuropsychiatry (SCAN) is a manual published by the World Health Organization designed to assess, measure, and classify the psycho-pathology and behavior associated with the major psychiatric syndromes of adult life. SCAN had its origins in the 9th edition of the Present State Examination (PSE 9). SCAN consists of 4 components: the 10th edition of the “Present State Examination” (PSE 10), the “Item Group Check List,” the “Clinical History Schedule,” and the “Glossary of Differential Definitions.” Only the first 3 were reviewed. The PSE 10, which forms the greater part of SCAN, covers phenomenology. The “Item Group Check List” is a method of obtaining information from case records and informants other than the patient himself or herself. The “Clinical History Schedule” is a method of checking or entering data relevant to the broader clinical and social history.

The PSE itemizes various domains and categories of psychopathology. For each phenomenological category an appropriate probe question is provided. The PSE does not give detailed definitions. These are contained in the “Glossary of Differential Definitions” which was unfortunately not available for review. This is regrettable since the SCAN can only be fully appreciated in the context of the glossary.

The SCAN is designed for epidemiological research rather than day-to-day clinical care. Data from the schedules are intended to be entered into a computer algorithm (C ATEGO-5) which processes the data. The output is a series of options including a range of profiles of symptoms, an index of definitions and ICD-10, and DSM-III-R diagnostic categories.

Interviewers who use SCAN must first address those factors that would interfere with access to psychopathology or indicate a need to adopt specific interview strategies. These include severe language disorders, cognitive impairment, severe behavioral disturbance, uncooperativeness, or the likelihood of a premature termination. The PSE 10 rating scales address various domains and categories of psychopathology. The domains contain overlapping phenomenological categories that can be confusing. For example, depersonalization and derealization, which are rightfully disturbances of perception, are also included in the domain of nervous tension. While this may be useful for research purposes and computerized programs, overlapping phenomenological categories muddy the analysis of the mental state. This is akin to describing motor weakness in a neurological patient within the domain of sensory changes. It is preferable to keep phenomenological categories within their rightful domains. Elicited psychopathology can then be extracted and linked together within the context of a biopsychosocial framework to reach a diagnosis.

The domains of the mental state identified by the PSE include: somatic symptoms, nervous tension, panic, anxiety and phobia, obsessional symptoms, depressed mood and ideation, thinking, concentration, energy and interests, body functions, eating disorders, expansive mood and ideation, alcohol and substance abuse, language difficulties, perceptual disorders other than hallucinations, hallucinations, subjectively described thought disorder and experience of replacement of will, delusions, cognitive impairment and/or decline, motor and behavioral phenomenology, observed affect, speech abnormalities, and social impairment.

SCAN contains a separate section for evaluating stress-causing acute reactions and posttraumatic stress disorders, the course of schizophrenia as described by either DSM-III-R or ICD-10, acute psychosis, induced psychotic disorder, schizotypal disorder, simple schizophrenia (an ICD-10 but not a DSM-III-R diagnosis), and the negative syndrome of schizophrenia. The latter has been included in SCAN for research purposes.

The section on cognitive impairment and/or decline includes the well-known Mini-Mental State Examination (MMSE) as well as the less well-known Verbal Trails Test. This section also contains probes to assess language, calculation, praxis, abstraction, fiind-of-knowledge, frontal-sub-cortical function, and level of consciousness. The section on dementia includes specific etiologies such as Alzheimer disease and Parkinson disease.

SCAN was developed by an international panel of researchers. Various groups of collaborators were responsible for the design and field trials of particular sections of SCAN. This presumably accounts for the lack of integration and the overlap of phenomenological categories across various psychopathological domains. In addition SCAN, unlike PSE 9, shifts out of the context of the mental state examination and includes sections that rate specific psychiatric disorders and disease course as well as identifies specific etiologies. SCAN is, therefore, much more than a rating scale for the mental state examination. Users of the SCAN may find this confusing and would be wise to look elsewhere for a clear and integrated conceptual understanding of the various domains and categories of the abnormal mental state. Nonetheless SCAN does list much of the psychopathology of mental disorders and can be used as a reference by clinicians to enrich and polish their own mental state evaluations.

Concise Guide to Neuropsychiatry and Behavioral Neurology

Concise Guide to Neuropsychiatry and Behavioral Neurology

JL Cummings and MR Trimble

Washington DC: American Psychiatry Press Inc; 1995.275 p

Psychiatry is heading, willy-nilly, down the subspecialty route. Child, geriatric and forensic psychiatry are already recognized as subspecialties, and others such as psychotherapy and consultation-liaison psychiatry are following closely. Unfortunately, subspecialization is progressing in a disorganized manner, and this leads related subdisciplines such as neuropsychiatry and consultation-liaison psychiatry to evolve in parallel. Often, little effort is made to cohere or even to collaborate.

The authors of this small volume define neuropsychiatry and behavioral neurology as “clinical disciplines devoted to understanding and treating behavioral disturbances associated with brain dysfunction” (p 1). This definition seems restrictive and appears to rule out, by definition, the psychosocial aspects of neurological practice. Therefore, neuropsychiatry, according to these authors, does not follow the biopsychosocial model. The first author is a professor of psychiatry and neurology at the University of California at Los Angeles (UCLA) School of Medicine, and the second is a professor of behavioral neurology at the Institute of Neurology, London, England.

Initial chapters are devoted to assessment, neurobiology and psychiatric syndromes. The rest of the book is devoted to neurological syndromes such as epilepsy, dementia, stroke and head injury. Each chapter is concise, and frequent tables list and summarize relevant points. The text is clear, readable and nonrepetitive. No references are given in the text, but there is a useful reading list at the end of each chapter.

Despite the authors’ restrictive definition, I was surprised by the total absence of any reference to somatoform disorders or to the psychosocial aspects of neurology. Somatoform disorders form at least 14% of a neurologist’s practice (Mai 1995). One would have thought that any clinical textbook that included the word “behavior” in its title would also cover the field of illness behavior. However, one looks in vain in this book for any recognition of the existence of illness behavior, conversion or somatization. Even the brief description of pseudoseizures fails to mention that they may have a conversion basis. The authors do not explain the reasons for this omission, but it is likely the result of their chosen focus on neurological disease.

This approach reminds me of the old story about the drunk who returns home late at night to find he has lost the key to his front door. He then confines his search to the area around the street light, because “that’s where the light is”. The authors of this volume have similarly chosen to ignore the darker areas of neurology which, inspite of themselves, affect the clinical practice of this discipline.

In other respects, the book provides a useful and concise description of the field within die confines set by the authors. It could be of value to residents, psychiatrists and neurologists with an interest in this field. It is expensive for a soft-cover book.

Synopsis of Neuropsychiatry

Synopsis of Neuropsychiatry

SC Yudofsky and RE Hales, editors

Washington DC: American Psychiatric Press; 1994. 641 p

This paperback is a synopsis of the American Psychiatric Press Textbook of Neuropsychiatry, which was first published in 1987 (a second edition has subsequently been published). The Synopsis of Neuropsychiatry is designed to condense most chapters from the second edition, and its content is aimed at medical students and residents in psychiatry and neurology.

The book is divided into 5 sections: the basic principles of neuroscience, neuropsychiatric assessment, neuropsychiatric symptomatologies, neuropsychiatric disorders, and neuropsychiatric treatments.

The section on basic principles of neuroscience includes chapters on cellular and molecular biology of the neuron, and on human electrophysiology. The chapter by Daniel Tranel on functional neuroanatomy from a neuropsychological perspective is particularly well done. These chapters are all well organized and plentiful diagrams add interest and clarity.

The neuropsychiatric assessment section includes chapters on bedside neuropsychiatry, neuropsychological evaluation, electrodiagnostic techniques, brain imaging, and epidemiology and genetics. The chapter on bedside neuropsychiatry by Fred Ovsiew is an excellent summary of the major symptoms and signs of neuropsychiatric disorders. The chapters on electrodiagnostic techniques and brain imaging are also good overviews. I found the chapter on epidemiology and genetics too technical when describing linkage analysis and molecular approaches to the investigation of various neuropsychiatric diseases such as Huntington’s Disease and schizophrenia.

The third section on neuropsychiatric symptomatologies includes chapters on differential diagnosis in neuropsychiatry, neuropsychiatric aspects of pain management, and delirium. Chapters on neuropsychiatric aspects of aphasia and related language impairments, and neuropsychiatric aspects of memory and amnesia are also part of this section. The chapter on differential diagnosis by Richard Strub and Michael Wise has an excellent algorithm on the approach to the patient with memory loss, as well as an informative and concise table on common focal behavioral syndromes and their localization. The chapter on pain management by William Brouse and David Spiegel focusses on neurological mechanisms of pain and neuropharmacology but could be more clinically oriented. Delirium is well covered by Michael Wise and George Brandt. Frank Benson provides a superb chapter on aphasia, which presents a complicated topic clearly and succinctly. The chapter on neuropsychiatric aspects of memory and amnesia by Arthur Shimamura and Felicia Gershberg describes the neural and biochemical mechanisms of memory very well, and outlines some clinical syndromes. However, it would benefit by a section on the differential diagnosis and investigation of the patient with memory disturbance.

The next section has 12 chapters on specific neuropsychiatric disorders: traumatic brain injury, epilepsy, sleep, cerebral vascular disorders, brain tumors, human immunodeficiency virus, endocrine disorders, poisonous and toxic disorders, alcohol-induced organic mental disorders, degenerative dementias associated with motor dysfunction, Alzheimer’s Disease and other dementias, and the neuropsychiatry of schizophrenia. There are particularly comprehensive and clinically focussed chapters on sleep (by Thomas Neylan, Charles Reynolds and David Kupfer), cerebral vascular disorders (by Sergio Starkstein and Robert Robinson), Alzheimer’s Disease (by Jeffrey Cummings), and the neuropsychiatry of schizophrenia by Henry Nasrallah. There is little, in any chapter, written on the neuropsychiatric aspects of multiple sclerosis despite its prevalence. Other missing topics include autistic disorders and mental retardation, neuropsychiatric aspects of street drug abuse, and chronic fatigue syndrome.

The final section on neuropsychiatric treatments includes chapters on psychopharmacological treatment in neuropsychiatry, psychotherapy for neuropsychiatric disorders, cognitive rehabilitation and behavior therapy, stress and coping in family caregivers, and ethical and legal issues in neuropsychiatry. The chapter on psychopharmacology by Steven Dubovsky is comprehensive and well organized. I found the chapter on psychotherapy too long and wordy, although the tables nicely summarize the lengthy discussion in the text. The chapter on cognitive rehabilitation and behavior therapy by Mark Lovell and Christopher Starratt is a well-written overview, and serves as a good introduction to this topic. Stress and coping in family caregivers is covered mostly by discussing theorical models with little attention to clinical issues. Ethical and legal issues in neuropsychiatry are well covered in the chapter by Robert Simon.

Overall, this is a strong textbook which provides a solid overview of neuropsychiatry. The authors are all recognized neuropsychiatry experts. Every chapter is well referenced, which enables the reader to investigate any topic in more depth, if necessary. A strength of almost every chapter is the liberal use of tables, diagrams and figures. Unfortunately, several chapters contain diagrams and figures that require colour to be useful, such as figures of PET and SPECT scans. The reader is referred to The American Psychiatric Press Textbook of Neuropsychiatry, second edition, for full-color figures. This is extremely irritating, and it is unlikely that many readers will have ready access to the larger textbook when reading this chapter, thus losing the benefit of illustrations. I suggest that the publisher consider adding full-color figures even if it increases the cost of the Synopsis of Neuropsychiatry.

This book will be very useful for residents in psychiatry, particularly during a rotation in consultation-liaison psychiatry, and also for neurology residents and neuropsychology interns. Medical students will benefit from this book during their rotations in psychiatry and neurology. It will also be useful to clinical psychiatrists involved in inpatient and consultation-liaison psychiatry, although other textbooks will be necessary if an indepth look into a particular area is desired.

Neurobiology of Learning, Emotion, and Affect

Neurobiology of Learning, Emotion, and Affect

John Madden IV

New York, NY: Raven Press, 368 pp, 1991

This book comes at a time of progress and exciting new discoveries in the field of research involving the neural basis of learning, emotion and affect. The study of learning and memory has flourished for many years within the neuroscientific community. Although long neglected by all but a handful of neuroscientists, emotion and affect have begun to attract attention. A clear summary of the status of this recent work is therefore particularly welcomed.

The book is divided into three parts. The first part is devoted to recent advances in the research of the neural mechanisms of fear conditioning, in both invertebrates and vertebrates. Most exteroceptive stimuli we encounter in our life are affectively “neutral”. However, they can take on emotional properties and elicit emotional reactions, such as defence or approach responses, through association with other stimuli or events that are affectively charged. It is possible to study experimentally the ways in which the brain forms such associations through the use of Pavlovian conditioning techniques, whereby a “neutral” stimulus, the conditioned, or conditional stimulus (CS), is paired with a biologically significant (affectively charged) stimulus, the unconditional or unconditioned stimulus (US).

Pavlovian conditioning procedures have been used to study the biology of learning in many species. Whether or not it is reasonable to speak of Pavlovian conditioning as a process of emotional learning is debatable for invertebrates, many vertebrates, and even many mammalian species, if emotion is restricted to subjective, experiential factors. However, if by emotion we also mean the neural mechanisms by which stimuli are evaluated for their significance (LeDoux 1990), it is possible to view all animals as engaging in a form of emotional processing. What is different about humans and possibly higher primates is that the emotional processing of stimulus significance becomes represented as conscious content. This view is advantageous in that it places emotional processes on a continuum and allows for studies of emotion throughout the animal kingdom.

In the Aplysia model, described in detail by Hawkins, the cellular mechanisms and neural loci responsible for associative learning are, without a doubt, understood more than in any other animal model. Are the same basic mechanisms discovered in this simple model in operation also in more complex organisms? Hawkins believes that classical conditioning in Aplysia, Hermissenda, cat and rabbit involve the same neural mechanisms. In Aplysia, the US plays a modulatory role in stimulating the facilitator neurons. The convergence of this input with the appropriate CS input (the one that was paired with the US) increases presynaptic facilitation and produces classical conditioning. A similar mechanism is acting in vertebrate models as well, Hawkins suggests. The aminergic and cholinergic systems in the vertebrate nervous system can behave like the facilitator neurons of Aplysia. One challenge for the future is to test this simple and attractive theory.

Another elegant invertebrate model is Drosophila melanogaster. An advantage of this model is the possibility of using genetic tools. In recent years, the isolation of mutations that affect an aversive conditioning task in the fruit fly has considerably increased our understanding of the molecular mechanisms of learning and memory. Tim Tully reminds us that with Drosophila research, we probably have the only evidence that short-term and long-term memory are indeed two genetically distinct processes.

Our understanding of the molecular and underlying elementary neural mechanisms which make learning possible in an individual is far less developed in vertebrate models. In recent years, however, simple vertebrate model systems have been worked out, and important neural structures and pathways essential in learning have been shown. It now appears that different types of learning are mediated by different but, in some cases, overlapping neural circuits.

One promising vertebrate model is the conditioned fear-potentiated startle paradigm. In this behavioral model, the conditioned stimulus (usually a light) is paired with a shock and startle response elicited by a noise burst in either the presence or absence of the light. If the startle response is greater when elicited in the presence of the light, the fear-potentiated startle has occurred.

The role of the amygdala in this reflex has been demonstrated by Davis and collaborators; in this book they review the current state of affairs. The amygdala is the centerpiece of the neural pathway involved in fear-potentiated startle, as well as in other fear conditioning situations (Kapp et al 1990; LeDoux 1990). Davis and collaborators show that the activation of the amygdala from the visual conditioned stimulus pathway triggers the startle reflex pathway. The central nucleus of the amygdala carries this out through its connection with the nucleus reticularis pontis caudalis (a nucleus in the startle circuit). Davis and colleagues believe that the visual input comes to the amygdala through cortical pathways. However, findings from our laboratory suggest that visual fear conditioning can be mediated by subcortical visual inputs to the amygdala (LeDoux 1990).

There is a general consensus about the involvement of the amygdala in mediating the acquisition of autonomic responses in the aversive classical conditioning. These responses are defined as “non-specific” and include heart rate, generalized motor activity (freezing, startle response) and skin resistance. They all develop rapidly after a few trials, sometimes requiring just a single contingent pairing. “Specific” responses, on the other hand, are discrete, skeletal muscle responses elicited by specific aversive stimuli. They are much slower to develop and are more specifically adaptive for the organism.

Steinmetz and Thompson describe how the cerebellum, in particular the interpositus nucleus, is an important site for the acquisition of these discrete, specific responses. Using a multi-technique approach (recording, stimulation, lesion studies) they developed a detailed anatomical map of the circuitry involved in the adaptation to aversive events for these behavioral responses. According to Steinmetz and Thompson, the cerebellum plays an “informational” role in the learning of the organism. It is activated in conjunction with the aversive system that involves higher brain regions (the amygdala, for example). These two systems in the brain are distinct, but they interact in the adaptive learning phase. The US pathway activates both systems. And while the cerebellum appears to play an important role in learning the specific response, recent studies also suggest that the amygdala is involved in the early phases of learning. The final attempts to relate these ideas to the popular Rescorla-Wagner learning theory.

Part II of the book deals with experimental situations in which the animal is allowed little or no control over the aversive stimulation How do the subjects cope with stressful events when species-specific defense responses are not helpful? What kind of behavioral and biochemical changes will stressful events elicit? Results from these experimental studies are particularly valuable for their clinical implications. Weiss, using an uncontrollable shock paradigm, suggests in fact that stressed animals show symptoms closely corresponding to those developed by depressed individuals. Moreover, the author proposes that stressful events (for example, uncontrollable shock) elicit both anxiety and behavioral depression. In his analysis, Weiss shows how the locus coeruleus seems to be a key structure in the neurochemical unbalance produced by the uncontrollable shock.

Cognitive deficits may also occur as part of the response to stress. Animals that are exposed to shocks that they cannot avoid or escape later fail to escape shock in a situation in which escape is possible. They also fall well behind control animals (that were allowed to escape or avoid shock in the first phase of the experiment) in Y-maze or water-maze learning tests. Some researchers have explained these results in terms of a simple motoric impairment: the shocked animals learn a coping response in the new situation, but they cannot perform it. Maier rejects this hypothesis; his work suggests that inescapable shock gives rise to learning deficits that cannot be explained by a motor activity deficit.

However, the impairment is not the result of associational learning between the first phase of the experiment and later test situations, as it was suggested in the early explanations of this phenomenon. What is impaired in these subjects, according to Maier, is the capacity to attend the salient external cues; the deficit is then a cognitive one, not an associative one (the learned helplessness hypothesis). Whether this cognitive deficit will be connected to some neural loci or biochemical systems will have to be determined in future studies.

More complex issues of depression and human affect disorders, which involve multiple interactions between emotional and cognitive systems operating at conscious and unconscious levels, are difficult to probe with vertebrates too distant from us in the evolutionary ladder and in social habits. Suomi describes a primate model of affective disorders, the separation model. Humans share over 90% of non-replicated DNA material with higher primates. In addition, the behavior of these animals is characterized by advanced and dynamic social interactions among members of the same species. Rhesus monkeys, in particular, have been studied extensively in the wild and in laboratory settings. Stressful events caused by social relationships among individuals closely resemble human social life. Separation from an attachment object, such as a mother or a loved conspecific, produces profound behavioral and physiological effects, both in the wild and in the laboratory. The evidence of individual differences in these animals makes this model particularly interesting. Not all subjects respond to the same social separation in the same manner. There is also consistency in this behavior in individuals. The same monkeys “at risk” are more readily aroused by and behaviorally fearful of other stressful events. Having individuated the groups “at risk” in the rhesus monkeys population, it may be possible to forecast or even prevent the affective disorder. The “separation/risk” model in monkeys, as Suomi defines it, seems to be extremely promising for improving our understanding of the psychobiology of human affective disorders.

There is evidence from this primate model that the noradrenergic system is involved in mediating depressive states. Matthysse reaches the same conclusion in his analysis of mood disorders. In particular, the locus coeruleus, an important source of forebrain noradrenalin, is advanced as a candidate for depression, as Weiss also proposed for the helplessness model. According to Matthysse, this nucleus becomes activated by excited unhappy memories, which are the result of early loss or other traumatic events. Cerebral activation is then reduced by the increased firing of the locus coeruleus. At this point, physostigmine, the cholinergic agent, enters the circuit to produce the physiological symptoms of depression. In Matthysse’s view, while the memories are the primary cause of noradrenergic changes, the biogenic amines are only the effectors in this theory. Matthysse points out that human studies suggest that decreased cerebral activation is produced by physiostigmine in normal subjects (for example, the subjects feel “apathy, slowness of speech and movement”). Physiostigmine physiological symptoms closely resemble those of depression. In his fascinating theory, however, Matthysse does not tell us where these memories may be stored in the brain or why, at a certain point, they overflow to reach the locus coeruleus. Also, it will be interesting to try to define the role of anxiety in this context. Under identical conditions of stress some people respond only with anxiety; do they have the capacity to deal with the unhappy memories activation in a different way? Interesting questions arise from this theory that only future experiments can elucidate.

Control over stressors is a critical factor that influences biological functions which regulate adaptive and maladaptive behaviors. Bandura states that the ability to control stress effects is the principal factor that makes a person cope with stress events. It is the ability to control the stress effects that prevents the release of stress-related hormones or the impairment of the immune system. With the support of human quasi-experimental studies, Bandura describes the effect of being able to gain control over the stressful situation. For instance, catecholamine levels in phobic patients dropped after allowing them to acquire controlling efficacy. Pain tolerance was increased in normal subjects when there was self-efficacy, even in those subjects to whom naloxone was administered to block opioid activation. Self-efficacy mechanisms play an essential role in the individual’s well-being. Bandura’s theory proposes an entire psychological approach to deal with stressful events that deteriorate our biological systems. This approach provides an intelligent stimulus to operate in the sphere of human maladaptive behaviors with “clean” psychological tools but with an attentive eye on the neurobiological domain.

Part III of the book explores broader issues in the field of emotion and affect and presents two models. Gray describes three systems that control emotional behavior. Each of these systems is associated with a particular area in the brain. One of these systems, the behavioral inhibition system, is thought by Gray to be centered around the hippocampal formation. This system is responsive to stimuli associated with punishment or with the conditioned aversive stimuli and is involved in increasing the level of arousal and increasing attention to the environment to cope with the new situation. Anxiolytic drugs affect the septohippocampal system, and lesions of this system lead to a behavioral syndrome similar to that seen after the administration of anxiolytic drugs. These results are the strong-hold of Gray’s theory. The amygdala, a structure that has long been considered to play a pivital role in fear, including fear learning, is not included in the behavioral inhibition system. It is involved instead in the second system, the fight/flight system, which is responsive to unconditioned punishment and non-reward, that is, to issue commands either for fight or for flight depending on the context and type of punishment received. Gray dismisses fear conditioning studies as irrelevant to the problem of anxiety and relegates them to elicitor of a more species-specific type of defence or attack responses. We do not agree with such a view. Nevertheless, Gray’s model is commendable in its breadth and attempt to synthesize divergent findings into a unified theory of anxiety. The second model uses the opponent-process theory to explain a large set of affective phenomena, taken from everyday life and experimental settings. This model states that it is possible to produce acquired motives by non-associative mechanisms alone. The mechanism is repetition, not conditioning (association). Solomon believes that his approach can explain food intake, drug addiction and related phenomena that Pavlovian conditioning is not able to explain. An important question that the author raises is whether or not the opponent-process states are predictable. He is convinced that they are and analyzes the process of food intake and obesity following the logic of opponent-process theory.

Neurobiology of Learning, Emotion, and Affect is a well organized, multi-disciplinary book. It presents a range of approaches and contributions. The literature on behavioral neuroscience, in general, has increased tremendously in the last few years. Moreover, there is a growing interest in research on emotion, which has been somewhat neglected in the age of cognition. This book will help bring research on emotion into the limelight. The book will be very useful as an introduction to research on the biology of emotion and learning and will also be useful as reference point for future research.

Refractory Depression

Refractory Depression

J.D. Amsterdam

New York, NY: Raven Press, Vol 2 in Advances in Neuropsychiatry and Psychopharmacology, 249 pp., 1991

In spite of the proven efficacy of antidepressants in the treatment of major depressions, clinicians have recognized over the past 30 years that at least 30% of their patients fail to respond adequately to treatment. As depression is associated with definite morbidity and mortality, it is surprising the less than adequate attention has been given by researchers both in academia and the pharmaceutical industry to the phenomena of “refractory depressions.” A number of methodological issues have confounded research in this important area. Just a few of the many factors that researchers have to account for in dealing with the phenomena of “failure to respond” are the lack of agreement on a clear definition of “response”; the recognized heterogeneity of depressions; and, the absence of clear guidelines for alternative approaches. In that light, this book in an important contribution for both clinicians and researchers. Its 24 chapters are a broad spectrum of issues important for the current understanding of the phenomena of refractoriness as well as clinical and experimental approaches in dealing with it. As in any book with multiple contributors, the quality of chapters varies widely.

Obviously, the book concentrates on biological issues important in the understanding of the pathophysiology of depression as well as the number of biological treatment strategies that have proved effective in the management of depression. The book would have benefited from a chapter on psychosocial aspects and the possible role of “extrapharmacological factors” as adjunctive approaches in manipulation of treatment resistance. However, overall the book provides valuable information for both researchers and clinicians on a clinically important issue.