PSYCHIATRY – Introduction

1. PSYCHIATRY – Introduction Dr. Hakan Atalay Yeditepe University Hospital

7. History The first specific description of a mental illness appeared in approximately 3000 bc in a depiction of senile deterioration ascribed to Prince Ptah-hotep. The syndromes of melancholia and hysteria appeared in the Sumerian and Egyptian literature as far back as 2600 bc. In the Ebers papyrus (approximately 1500 bc), senile deterioration and alcoholism were described. In India, in approximately 1400 bc, a classification of psychiatric disorders was included in the medical classification system of Ayur-Veda.

8. History Hippocrates (approximately 460 to 370 BC) is usually regarded as the one who introduced the concept of psychiatric illness into medicine. His writings described - acute mental disturbances with fever (perhaps delirium), - acute mental disturbances without fever (probably analogous to functional psychoses but called mania), - chronic disturbance without fever (called melancholia), - hysteria (broader than its later use), and - Scythian disease (similar to transvestism).

9. History Philippe Pinel (1745 to 1826), a French physician, simplified the complex diagnostic systems that preceded him by recognizing four fundamental clinical types: mania (conditions with acute excitement or fury), melancholia (depressive disorders and delusions with limited topics), dementia (lack of cohesion in ideas), and idiotism (idiocy and organic dementia).

10. History Karl Ludwig Kahlbaum (1828 to 1899), a German descriptive psychiatrist who foreshadowed Emil Kraepelin, introduced the concepts of (1) the temporary symptom complex, as opposed to the underlying disease, (2) the distinction between organic and non-organic mental disorder, and (3) the consideration of the patient's age at the time of onset and the characteristic development of the disorder as bases for classification.

11. History Kraepelin (1856 to 1926) synthesized three approaches: the clinical-descriptive, the somatic, and the consideration of the course of the disorder. He viewed mental illnesses as organic disease entities that could be classified on the basis of knowledge about their causes, courses, and outcomes.

12. History He brought the manic and depressive disturbances together into one illness, manic-depressive psychosis, and distinguished it, on the basis of its periods of remission, from the chronic deteriorating illness called dementia praecox, which Eugen Bleuler later renamed schizophrenia.

13. History Sigmund Freud (1856 to 1939), after studying hysteria, the prototypical neurosis, went on to divide the neuroses into the actual neuroses, the result of dammed-up sexual excitation, and the psychoneuroses, the result of unconscious conflict and compromise symptom formation. Freud recognized only the following subtypes of neurosis: anxiety neurosis, anxiety hysteria (phobia), obsessive-compulsive neurosis, and hysteria.

14. History DSM-III was published in 1980. Seven years later, DSM-III-R was published. Less than 1 year after the publication of DSM-III-R, plans were announced for the publication of DSM-IV. Delayed by 2 years, DSM-IV was ultimately published in 1994.

15. DSM-III DSM-III was the first official diagnostic system to specify inclusion and exclusion diagnostic criteria. Diagnostic reliability is better, and this is of benefit to researchers attempting to replicate another researcher's findings and to clinicians who can communicate more effectively with one another. DSM-III was the first official psychiatric classification to introduce a multiaxial evaluation system in which different domains of information are described on five different axes.

16. Multiaxial system Axis I consists of all clinical disorders, except for personality disorders and mental retardation, both of which are reported on Axis II. Prominent maladaptive personality traits that do not meet criteria for a specific disorder and defense mechanisms are also noted on Axis II. Axis III is for general medical conditions that might be relevant to understanding or managing the patient's psychiatric disorder. Axis IV is for noting psychosocial and environmental problems that are relevant to the diagnosis, treatment, and prognosis of Axis I and Axis II disorders. Axis V is the global assessment of functioning (GAF) scale, a 100-point rating based on symptom severity, social functioning, and occupational functioning.

17. Groups of Conditions in DSM-IV-TR Disorders usually first diagnosed in infancy, childhood, or adolescence Delirium, dementia, amnestic, and other cognitive disorders Mental disorders due to a general medical condition Substance-related disorders Schizophrenia and other psychotic disorders Mood disorders Anxiety disorders Somatoform disorders Factitious disorders Dissociative disorders Sexual and gender identity disorders Eating disorders Sleep disorders Impulse-control disorders not elsewhere classified Adjustment disorders Personality disorders Other conditions that may be a focus of clinical attention

18. www.dsm5.org

19. The human brain contains approximately 100 000 000 000 nerve cells or neurons, with each having appr. 10 000 synapses.

21. (1) the cell body or soma, which contains the nucleus and can be considered the metabolic center of the neuron; (2) the dendrites, processes that arise from the cell body, branch extensively, and serve as the major recipient zones of input from other neurons; (3) the axon, a single process that arises from a specialized portion of the cell body (the axon hillock) and conveys information to other neurons; and (4) the axon terminals, fine branches near the end of the axon that form contacts (synapses) generally with the dendrites or the cell bodies of other neurons, release neurotransmitters, and thereby provide a mechanism for interneuronal communication.

23. Projection neurons have long axons and convey information from the periphery to the brain (sensory neurons), from one brain region to another, or from the brain to effector organs (motor neurons). In contrast, local circuit neurons or interneurons have short axons and process information within distinct regions of the brain.

24. Neurons can also be classified according to the neurotransmitters they contain (e.g., the dopamine neurons of the substantia nigra).

25. Brain also contains several types of glial cells, which are at least ten times more numerous than the neurons. Oligodendrocytes and Schwann cells, are relatively small cells that wrap their membranous processes around axons in a tight spiral. (The resulting myelin sheath facilitates the conduction of action potentials along the axon.) Astrocytes, the most numerous class of glial cells, appear to serve a number of functions, including participation in the formation of the blood-brain barrier, removal of certain neurotransmitters from the synaptic cleft, buffering of the extracellular potassium (K+) concentration, and, possibly a nutritive function as well. The third class of glial cells, the microglia, are actually derived from macrophages and function as scavengers, eliminating the debris resulting from neuronal death and injury.

28. THE INTERNAL AND EXTERNAL WORLDS Brain is connected to two “worlds”: the world within us, the internal milieu of the body; and the world outside us, the external environment. In a profound sense, the principal task of the brain is to mediate this divide -to mediate between the body (the vegetative functions) and the ever-changing world around us.

29. EXTERNAL WORLD The brain is connected to the outside world in two main ways. The first is through the sensory apparatus; the second is through the motor apparatus. This is how we receive information from the world and how we act on the world.

30. Perceiving and representing the external world Sensation is generated by specialized sensory receptors (in the eye, ear, etc.) that transform selected physical features of the environment into nerve impulses and send the resultant information to the brain: vision, hearing, somatic sensation,.. Taste and smell are “chemical” in nature.

31. Projection and Association Cortex In the projection cortex the nervous tracts derived from the various sensorimotor organs literally project the receptor and effector surfaces of those organs onto the cortex, forming tiny functional maps of the body all over the brain. The pattern of neural activity representing the information in the primary cortex still retains its original topographic organization with the receptive field of the sense organ.

32. Posterior and anterior half of the brain The posterior half of the hemispheres of the brain is traditionally defined in neuropsychology as a functional unit for reception, analysis, and storage of information. Anterior half is defined as the functional unit for programming, regulation, and verification of action.

33. FUNCTIONAL BRAIN SYSTEMS Thalamocortical Systems Basal Ganglia System Limbic System

34. Talamocortical System The thalamus and its interactions with the cerebral cortex have primary importance in the sensory, motor, and associative functions of the brain. Moreover, the thalamus and its interactions with the cerebellar cortex are now known to be involved in cognition.

36. Basal Ganglia The basal ganglia, once thought of only as part of the motor system, is now known to be a complex system within itself, and plays a key role in the cognitive functions of the brain.

37. Limbic System In contrast to the thalamus and basal ganglia, the limbic system has long been associated with psychiatric symptoms because of its clear involvement in the experience and expression of emotions.

38. Emotions The internal milieu refers to the world of respiration, digestion, blood pressure, temperature control, sexual reproduction, and the like. These organs are responsible for the body's survival. Operation of the viscera is of critical importance for understanding the “inner world” in the psychological sense (i.e., the world of subjective experience). The operation of these systems forms the basis of our basic motivations or “drives”, and modifications in our drives are experienced as emotions.

39. Emotion Emotion is akin to a sensory modality -an internally directed sensory modality that provides information about the current state of bodily self, as opposed to the state of the object world.

40. Emotions and Visceral Systems

41. Basic emotions The seeking system (appetitive, dopamin) * The lust subsystem (endorphin) The rage system (serotonin) The fear system (NE) The Panic system (opioids) Play and other social emotions

42. Cortical tone and arousal Modifications in these internally directed brain systems also affect our level of consciousness in general. For this reason, the visceral component of the brain is traditionally defined as a functional unit for modulating cortical tone and arousal. Episodic memory also is inextricable from emotion and consciousness.

43. Hypothalamus Information travels up through the spinal cord from the interior of the body, reaches, in the first instance, the hypothalamus -which is the controlling mechanism of the autonomic nervous system. The hypothalamus is intimately connected with the group of structures known as the limbic system. The functions of the internal milieu are “projected” onto the hypothalamus.

44. Hypothalamus The hypothalamus relays this information to a range of other structures throughout the limbic system and the rest of the brain. In this way, the prevailing state of the body is linked with concurrent objects in the external world, and these links are committed to memory. Then limbic system as a whole may be regarded as the “association” area for visceral information.

45. Feeling The perception of visceral information is registered consciously as feelings of emotion and (via association) as reminiscences, in the form of: “I saw that, and it made me feel like this”.

46. Executive control: PFC, superstructure over the brain. An extremely important aspect of prefrontal lobe maturation involves the gradual development of inhibitory control over the stereotyped motor patterns released by the visceral systems of the brain. The developing prefrontal lobes also gain inhibitory control over emotionality and consciousness in general, thus providing the basis of directed thinking and attention, and so forth.

47. Neurotransmitters • There are four broad classes of neurotransmitter and neuromodulator substances in the brain: monoamines, amino acids, peptide neurotransmitters, and the much more recently discovered neurotrophins (also known as neurotrophic factors). • Two additional neurotransmitters that do not fit into these four major classes are the gas nitric oxide and the purine-related neurotransmitters adenosine and adenosine triphosphate (ATP).

48. MONOAMINE NEUROTRANSMITTERS Serotonin Dopamine Norepinephrine ve epinephrine Histamine Acetylcholine

49. Monoamine Neurotransmitters The monoamine neurotransmitters, although present in only a small percentage of neurons localized in small nuclei of the brain, have enormous impact on total brain functioning because the diffuse projections of axons from these monoaminergic neurons can affect virtually every brain region.