Neurophysiology, Neurotransmitters, and the Nervous System PDF

NEUROPHYSIOLOGY, NEUROTRANSMITTERS, AND THE NERVOUS SYSTEM PSY3142 OUTLINE • The Nervous System • The Neuron • Neurotransmission Funny Cartoon Medication Talk Smiling Capsule Conversation Funny Pills Funny Drugs Gesticulating Chatter Stock Illustration - Download Image Now - iStock (istockphoto.c...

NEUROPHYSIOLOGY, NEUROTRANSMITTERS, AND THE NERVOUS SYSTEM PSY3142 OUTLINE • The Nervous System • The Neuron • Neurotransmission Funny Cartoon Medication Talk Smiling Capsule Conversation Funny Pills Funny Drugs Gesticulating Chatter Stock Illustration - Download Image Now - iStock (istockphoto.com) THE NERVOUS SYSTEM 3 PRESENTATION TITLE T HE NERVOUS SYST EM : PERIPHERAL NS Somatic Nervous System • Made up of all the sensory nerves from the conscious senses Autonomic Nervous System (ANS) • Concerned with sensory systems we are not usually aware of • Parasympathetic Nervous System • Acetylcholine • Sympathetic Nervous System • Fight-or-Flight Response • Epinephrine 5 parasympathetic sympathetic DIVISIONS OF THE AUTONOMIC NS DRUGS AND THE PNS 7 D EPR ES S ANT S, S ED A T IV ES , HY PNO TICS S T I MU L ANTS Tend to trigger the parasympathetic NS Tend to trigger the sympathetic NS DRUGS AND THE PERIPHERAL NS • Many drugs have the effect of engaging one or more systems in the peripheral NS 8 • Drugs are exogenous substances that work within our sensitive body systems often at levels or with effects that far exceed that of natural stimuli our bodies evolved to respond to THE NERVOUS SYSTEM: CNS Spinal Cord Brain • 100 billion neurons • Serves as a relay station • Brain works in concert, but has • Dorsal/back side (incoming messages many unique ‘divisions’ from sensory nerves to the brain) • Ventral/stomach side (outgoing messages to muscles) A human brain dissection – in pictures | Science | The Guardian Subjective experiences of psychoactive drugs are caused by the ability of a drug to alter normal functions of nervous system. The experience will be driven by which brain area or system is impacted. THE NERVOUS SYSTEM: HINDBRAIN, MIDBRAIN STRUCTURES HIND B R AIN • Connects to spinal cord • Structures: • Medulla oblongata • Pons • Cerebellum • Basic maintenance of arousal, survival, and coordination Stimulants increase hindbrain activity = alertness, increased brain activity, increased heart and respiratory rates Depressants decrease hindbrain activity = decreased activity, decreased heart and respiratory rates MI D B R AI N • Connects hindbrain - forebrain • Structures: • Reticular formation • Periaqueductal Gray (PAG) • Substancia nigra • Ventral Tegmental Area (VTA) • Innating/activating behaviour THE NERVOUS SYSTEM: FOREBRAIN STRUCTURES • • • • 11 Thalamus Hypothalamus Basal Ganglia Limbic System • Amygdala • Hippocampus THE NERVOUS SYSTEM: LIMBIC SYSTEM • Involved in control of motivations, emotions, memory • Hypothalamus • Medial Forebrain Bundle • Mesolimbic Dopamine System • Ventral Tegmental Area (VTA) • Nucleus Accumbens • Hippocampus • Amygdala and Septum 12 MAJOR FOREBRAIN STRUCTURES PREFRONTAL CORTEX • EXECUTIVE FUNCTIONS • MANY DRUGS CAN DECREASE ACTIVITY IN PREFRONTAL REGION • SHORT TERM – CAN IMPAIR EXECUTIVE FUNCTIONING TRANSIENTLY • LONG TERM – CAN DECREASE PERMANENTLY 14 NER V O U S S Y S T EM SUMMARY 15