Anxiety and Fear

last authored: Sept 2009, Dave LaPierre
last reviewed:

 

 

Introduction

Fear is the experienced reaction to accurately perceived danger.

Worry is uncontrollable negative thoughts about the past or future.

Anxiety is physiological tension and and arousal, leading to cognitive interpretation of threats and avoidance. It can be good in novel situations, heighten awareness, and help prepare for upcoming situations.

 

Normal fears include loud noises in infancy, strangers and separation in toddlers, monsters in 2-4 years, and bodily injury or danger in 6-10 years.

 

There is an inverted relationship between arousal and performance, however, and too much anxiety, for too long, can have significant negative effects. Excess energy leads to signs and symptoms of anxiety including:

 

Physical symptoms: generally sympathetic: tachcardia, tachypnea, diaphoresis, faintness

Affect: range from mild edginess to terror and panic

Behaviour: avoidance, compulsions

Cognitions: worry, apprehension, obsession, thoughts of emotional or physical harm

 

These also give rise to anxiety as an excess of energy swirling around (mine in my stomach). If my stomach neurons are swirling, what's happening to my brain?

 

The Case of...

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Differential Diagnosis

 

Temperament

behavioural inhibition (Kagan et al, 1988)

emotional intensity - high negative EI (anger, fear, sadness) correlates with anxiety disorders (Eisenberg, 1995)

 

Attachment

emerging evidence suggests genes are turned on/off with attachment

 

Parenting/Modeling

verbal and nonverbal communication

infants and children take cues from parent's faces, involving limbic and cortical pathways

"Kids very seldom listen to what you say, but the watch very carefully what you do" Morgan Freeman

parenting style...

Parental Anxiety

 

Cognition

...

 

Integrated Model

Genetic/constitutional vulnerability shaped by developmental experience, influenced by environment, and maintained by maladaptive cognitions and behaviours including avoidance responses.

 

An too much anxiety, improperly addressed, can lead to conditions such as:

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History and Physical Exam

  • history
  • physical exam

History

Physical Exam

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Investigations

  • lab investigations
  • diagnostic imaging

Lab Investigations

  • hyperthyroid
  • B12
  • mitral valve relapse, arrhythmias
  • hypoglycemia
  • hypoparathyroid
  • lung disease, ie asthma, COPD
  • phaeochromocytoma
  • seizures
  • PANDAS - Strep infection

 

Diagnostic Imaging

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Management

Avoidance is likely the most common response to anxiety, either behaviourally or psychially. While this can be helpful at times, avoidance can actually make aniety worse the next time the stimulus arrives.

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Pathophysiology

Alarm - locus coeruleus - central NA mechanism

Limbic System (ie amygdala) - scans the environment, monitors internal sensations, integrates cognitive and memory inputs and determines emotional valence

 

Basal ganglia and thalamus --cortical circuits - increased activity in caudate and orbital frontal cortex in OCD

 

stress response - HPA axis - increased cortisol release

 

hypothalamus releases CRH to anterior pituitary, which releases ACTH to adrenal cortex, releasing cortisol.

 

cortex - interprets internal state

 

Excitatory: NE, CRH

Inhibitory: 5-HT, GABA

 

 

Fear Pathways

the short route:

emotional stimulus is processed by sensory thalamus, which activates the amygdala and induces an emotional response

Fear can be influenced by the amygdala, in the limbic system.

 

long route:

sensory thalamus signals are processed by sensory cortex, and together with hippocampal accessing of memories the amygdala is activated

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Resources and References

 

 

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Topic Development

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authors:

editors:

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