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The Hijacked Brain Dennis M. Shaughnessy, MD ABAM The Springboard Center 200 Corporate Drive Midland, TX 79705 432-620-0255www.springboardcenter.org.

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Presentation on theme: "The Hijacked Brain Dennis M. Shaughnessy, MD ABAM The Springboard Center 200 Corporate Drive Midland, TX 79705 432-620-0255www.springboardcenter.org."— Presentation transcript:

1 The Hijacked Brain Dennis M. Shaughnessy, MD ABAM The Springboard Center 200 Corporate Drive Midland, TX www.springboardcenter.org

2 Addiction is not a character flaw or a sign of weakness, but a disease similar to other psychiatric diseases. Addiction is not a character flaw or a sign of weakness, but a disease similar to other psychiatric diseases. Its cause can be better understood by explaining the brains function during the addiction process.

3 ASAM American Society of Addiction Medicine Public Policy Statement: Short Definition of Addiction Addiction is a primary, chronic disease of brain reward, motivation, memory and related circuitry. Dysfunction in these circuits leads to a characteristic biological, psychological, social and spiritual manifestations. This is reflected in an individual pathologically pursuing reward and/or relief by substance use and other behaviors. Addiction is characterized by inability to consistently abstain, impairment in behavioral control, craving, diminished recognition of significant problems with one’s behaviors and interpersonal relationships, and a dysfunctional emotional response. Like other chronic diseases, addiction often involves cycles of relapse and remission. Without treatment or engagement in recovery activities, addiction is progressive and can result in disability or premature death.

4 Plasticity of brain function The fact that the brain changes permanently in regards to both internal and external stimulation. Psychopharmacology and Plasticity are beginning to provide an explanation of two characteristics associated with addiction: Tolerance & Withdrawal

5 At the very center of this model is the idea of the Pleasure Center (Olds & Milner, 1954 ) Using the brain stimulation paradigm, they came to the following conclusions: Electrical Stimulation of the brain could be experienced as pleasurable or rewarding An area known as the Nucleus Accumbens played a major role in this response

6 Drugs Work In The Midbrain NOT in the Cortex and how do we know this? … Midbrain Survival Unconscious No free will

7 James Olds, PhD ( ) Discovery of the reward system in the midbrain Discovery of the reward system in the midbrain Mice will self-administer electric currents to the Ventral Tegmental Area of the midbrain Mice will self-administer electric currents to the Ventral Tegmental Area of the midbrain They prefer the electrical stimulation over other survival rewards such as food They prefer the electrical stimulation over other survival rewards such as food

8 Subsequent experiments have demonstrated animals will take drugs or choose electrical stimulation of the brain at the expense of normal activities (i.e. eating, sleeping) and that they come to prefer an environment that they associate with the drug These experiments led to the formulation of the idea of a brain “Pleasure Center” This gives new meaning to the words “To Die for”

9 Much work subsequent to this has established that a class of neurotransmitters, known as the catecholamines, which includes Norepinephrine, Epinephrine, and Dopamine, seemed to be involved. Of particular interest, is the neurotransmitter, Dopamine, whose activation in the area of the brain known as the Nucleus Accumbens, appears to be a common denominator in many drugs of abuse.

10 Addiction Neurochemical #1 Dopamine All drugs of abuse and potential compulsive behaviors release Dopamine All drugs of abuse and potential compulsive behaviors release Dopamine Dopamine is the first chemical of a pleasurable experience and is at the heart of all reinforcing experiences Dopamine is the first chemical of a pleasurable experience and is at the heart of all reinforcing experiences DA is the neurochemical of salience (it signals survival importance) DA is the neurochemical of salience (it signals survival importance) DA signals reward prediction error DA signals reward prediction error Tells the brain “this is ‘better than expected’” Tells the brain “this is ‘better than expected’”

11 Addiction Neurochemical #2 Glutamate The most abundant neurochemical in the brain The most abundant neurochemical in the brain Critical in memory formation & consolidation Critical in memory formation & consolidation All drugs of abuse and many addicting behaviors effect Glutamate which preserves drug memories and creates drug cues All drugs of abuse and many addicting behaviors effect Glutamate which preserves drug memories and creates drug cues And … glutamate is the neurochemical of “motivation” (it initiates drug seeking) And … glutamate is the neurochemical of “motivation” (it initiates drug seeking)

12 DOPAMINE (DA) GLUTAMATE (Glu) All drugs of abuse and potential compulsive behaviors EFFECT Glu All drugs of abuse and potential compulsive behaviors EFFECT Glu Drug memories Drug memories Drug seeking Drug seeking “OK, I’ll remember” “OK, I’ll remember” “Fine, go and get it” “Fine, go and get it” Caudal (toward the tail) projections: Caudal (toward the tail) projections: PFC > NA PFC > NA All drugs of abuse and potential compulsive behaviors INCREASE DA All drugs of abuse and potential compulsive behaviors INCREASE DA Reward salience Reward salience “this is important!” “this is important!” “I really want this!” “I really want this!” Rostral (toward the nose) projections: Rostral (toward the nose) projections: PFC < NA < VTA PFC < NA < VTA

13 Nucleus Accumbens The release of Dopamine in this area seems to be related to the experience of intense pleasure

14 Nucleus Accumbens Nucleus Accumbens Ventral Tegmental Area (VTA) Ventral Tegmental Area (VTA) Prefrontal lobe Prefrontal lobe Limbic System Limbic System The Major Brain Areas Included in Addiction Are:

15 Studies have begun to compare how different activities affect the level of stimulation in this system with some very interesting results. Level of Intensity (from greatest to least) 1.Addictive Drugs 2.Sexual Activity 3.Eating 4.Exercise 5.Mediation, Spirituality, Deep thought, Art, Music, Nature, Socialization

16 Phineas Gage (1823 – 1860) Railroad construction foreman in Vermont Railroad construction foreman in Vermont Tamping rod driven through his skull by explosion Tamping rod driven through his skull by explosion Damage to Left Frontal Lobe and profound personality change Damage to Left Frontal Lobe and profound personality change “Gage was no longer Gage” “Gage was no longer Gage”

17 Ventral Tegmental Area –When stimulated, sends a signal (release of Dopamine) to the Nucleus Accumbens, and then, through the process of reuptake, ends this signal –Also is involved in what has become known, as an Anticipatory signal If this anticipation can’t be fulfilled, it might be replaced with another behavior If this anticipation can’t be fulfilled, it might be replaced with another behavior It is believed many forms of addiction begin here! It is believed many forms of addiction begin here!

18 Prefrontal Lobe –Willed actions are associated with this area, in contrast to “routine” or “automatic” tasks –Mediate or inhibit these relatively automatic or “fixed action patterns”, giving these behaviors certain flexibility and relative independence from the environment –Damage to this area can lead to Disinhibited behavior Disinhibited behavior Perseveration Perseveration Failure to assess consequences of ones actions Failure to assess consequences of ones actions Apathy Apathy Poor self-monitoring Poor self-monitoring

19 The Frontal Cortex The “Human” Brain The “Human” Brain Processes judgment, executive decision making, Processes judgment, executive decision making, Conscious emotions Conscious emotions Confers emotional meaning onto objects in the world Confers emotional meaning onto objects in the world Seat of the Self and Personality Seat of the Self and Personality “Love, Morality, Decency, Responsibility, Spirituality” “Love, Morality, Decency, Responsibility, Spirituality”

20 Executive Functioning Abstract thinking Abstract thinking Motivation for goal-directed activity Motivation for goal-directed activity Planning and problem-solving Planning and problem-solving Attention to tasks Attention to tasks Inhibition of impulsive responses Inhibition of impulsive responses Weighing consequences of future actions Weighing consequences of future actions Flexibility of responses (rule shifting) Flexibility of responses (rule shifting) Reflective decision-making Reflective decision-making Gives us the capacity to use past experience and knowledge to make sense of our current behavior

21 Failure of Executive Functioning Premature, unduly risky, poorly conceived actions Premature, unduly risky, poorly conceived actions Urgency Urgency Sensation seeking Sensation seeking Expressed emotions inappropriate to the situation Expressed emotions inappropriate to the situation Deficits in attention, lack of perseverance Deficits in attention, lack of perseverance Rapid responses without reflection or premeditation Rapid responses without reflection or premeditation Insensitivity to consequences Insensitivity to consequences Impulsive choice (increased delay discounting) Impulsive choice (increased delay discounting)

22 Limbic System

23 –Amygdala Primitive emotional responses (i.e. anger, surprise, fear, novelty) We recall how well we feel when we satisfy the addiction (i.e. good feelings around Christmas, Birthday, Hanukah, many years later) We recall how well we feel when we satisfy the addiction (i.e. good feelings around Christmas, Birthday, Hanukah, many years later) This at times overwhelms our logic! This at times overwhelms our logic! This explains why stimuli are associated with addiction (i.e. a bar, friends, neighborhood, drug paraphernalia) This explains why stimuli are associated with addiction (i.e. a bar, friends, neighborhood, drug paraphernalia) –Hippocampus Long-Term Potentiation (LTP): Physical process in which memories are formed- relies on the neurotransmitter Glutamate Long-Term Potentiation (LTP): Physical process in which memories are formed- relies on the neurotransmitter Glutamate

24 In addition to causing the experience of pleasure, the Dopamine system by virtue of its’ connections with the frontal lobe, can help explain some of the behavioral results of long-term substance abuse It has been suggested that the Mesocortical Dopamine System serves to take the prefrontal cortex “off line” during stressful events so that faster, more automatic or instinctive processes are mediated by the limbic system Putting It All Together

25 Acute depression of prefrontal lobe activity due to excessive inhibitory mesocortical dopaminergic neurotransmission evoked by drugs is increasingly accompanied over time by sensitization of dopaminergic transmission and perhaps chronic neurotoxic drug or dopamine actions on the frontal lobes, should significantly reduce the inhibitory control exerted by prefrontal cortical areas over posterior cortical and subcortical systems mediating reinforcement and automatization of behavior (Tiffany, 1990). Leads to impaired control over drug use and behavior in general

26 Newer theories of addiction suggest that over time, humans have either discovered or manufactured substances that hijack this system, creating addiction

27 In addiction, the drug hijacks the survival hierarchy and is so close to actual survival that it is indistinguishable from actual survival New #1 DRUG 2. EAT 3. KILL 4. SEX


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