Chapter 16 – Schizophrenia and the Affective Disorders

Chapter 16 – Schizophrenia and the Affective Disorders -...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 16 [1] Chapter 16 – Schizophrenia and the Affective Disorders Schizophrenia I. Description a. Serious mental disorder that afflicts 1 percent of the world b. Monetary cost is enormous c. It is ancient d. Schizophrenia – a serious mental disorder characterized by disordered thoughts, delusions, hallucinations, and often bizarre behaviors e. Categorized into positive, negative, cognitive f. Positive symptoms – a symptom of schizophrenia evident by its presence: delusions, hallucinations, or thought disorders g. Thought disorder – disorganized, irrational thinking h. Delusions – a belief that is clearly in contradiction to reality i. Grandeur and persecution and control i. Hallucinations – perception of a nonexistent object or event i. Auditory, smelling j. Negative symptoms – a symptom of schizophrenia characterized by the absence of behaviors that are normally present; social withdrawal, lack of affect, and reduced motivation k. Cognitive symptoms – a symptom of schizophrenia characterized by deficits in sustained attention, psychomotor speed, learning and memory, abstract thinking, and problem solving l. Negative and cognitive are not unique to schizophrenia m. Positive symptoms involve excessive activity in some neural circuits that include dopamine as a neurotransmitter n. Negative symptoms are the first to emerge, followed shortly by cognitive symptoms, positive symptoms follow several years later II. Heritability a. Appears to be heritable b. Several genes are involved or that having a “schizophrenial gene” imparts a susceptibility – does not mean you will necessarily get schizophrenia c. Another genetic factor is paternal age – children of older fathers more likely – mutation in spermatocytes d. Candidates for gene location have been found e. ncRNA may be important in this III. Pharmacology of Schizophrenia: The Dopamine Hypothesis a. Positive symptoms caused by a biochemical disorder b. Dopamine hypothesis – positive symptoms are caused by overactivity of synapses between dopaminergic neurons of the ventral tegmental area and neurons in the nucleus accumbens and amygdala c. Effects of Dopamine Agonists and Antagonists i. Chlorpromazine had good effects on schizophrneia ii. Diminish positive symptoms iii. Other drugs developed, block dopamine receptors iv. Antagonism of dopaminergic transmission
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Chapter 16 [2] v. Production of positive symptoms by dopamine agonists vi. Amphetamine, cocaine, methylphenidate, and L-DOPA vii. Most important systems of dopaminergic neurons begin in two midbrain nuclei: the substantia nigra and the ventral tegmental area viii. Mesolimbic pathway involved in schizophrenia ix. If reinforcement mechanisms were activated at inappropriate times, then inappropriate behaviors – including delusional thoughts – might be reinforced x. Euphoria during episodes, caused by hyperactivity of dopaminergic neurons involved in reinforcement d.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/27/2008 for the course PSYC 326 taught by Professor Chambers,lavond during the Spring '05 term at USC.

Page1 / 8

Chapter 16 – Schizophrenia and the Affective Disorders -...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online