Physiological Arousal and Anger

• Physiological arousal is a defining feature of anger
• Anger's key components are the cardiovascular, respiratory, and skeletal muscular systems
• Anger is metaphorically described as "hot fluid in a container"
• Residual arousal from anger events can transfer to future conflicts and intensify anger reactivity
• Unexpressed and undissipated anger can result in more exaggerated and prolonged cardiovascular responses to subsequent provocation, known as "excitation transfer" (Zillmann)
• Anger is the emotional component for attack preparation, triggering the "fight or flight" response
• Physiological arousal is intrinsic to anger
• Anger activation occurs in multiple physiological systems, including the:

Central Nervous System

• Brain & spinal cord components are activated by anger

Peripheral Nervous System

• Somatic & autonomic components are activated by anger

Endocrine System

• System is activated by anger

• System secretes hormones into the circulatory system

• The nervous system detects environmental changes and coordinates responses

• The central nervous system, including the brain and spinal cord, and the peripheral nervous system, are the main components

• The peripheral nervous system consists of the somatic nervous system (controls voluntary muscles) and the autonomic nervous system (controls involuntary muscles)

• The autonomic nervous system has sympathetic (expends energy) and parasympathetic (conserves energy) divisions

• The hypothalamus is the brain part of the limbic system that connects the nervous system to the endocrine system via the pituitary gland

• The Hypothalamus regulates metabolic processes of the ANS

• Command center for stress hormones

• Secretes corticotropin-releasing hormone and vasopressin

• The hypothalamic-pituitary-adrenal axis is set of glands that signal each other in sequence

• During alarm, the amygdala sends a distress signal to the hypothalamus

• Hypothalamus sends a signal to adrenal glands via the pituitary

• Adrenal medulla secretes epinephrine, triggering glucose release for fight or flight

• When the alarm persists, the HPA axis engages with the hypothalamus, pituitary, and adrenal cortex

• The pituitary signals adrenals to release cortisol

• The rising cortisol lowers as the threat fades; feedback loop w/ hypothalamus

• The hypothalamus vasopressin increases peripheral resistance and BP

Anger and Physiological Arousal

• Sensation of anger is highly correlated with physiological profile
• Increased facial temperature and flushing occurs
• Systolic and diastolic blood pressure increases
• Respiration increases
• Heart rate increases
• Skin conductance increases
• Muscle tension increases

Anger vs Fear

• Autonomic system arousal primarily engages through hormones of adrenal medulla (adrenaline & noradrenaline) and adrenal cortex (cortisol)

• Compared to fear, anger has stronger increases in diastolic bp, muscle tension, total peripheral resistance, and facial temperature

• Pituitary-adrenocortical and pituitary-gonadal systems indicate readiness or potentiation for anger responding

• John Hunter, an 18th-century surgeon and anatomist, was prone to wrath, which proved fatal

• A study of 313 hospitalized participants with acute coronary occlusion used the "Onset Anger Scale" to assess anger levels:

  • 1: Calm
  • 2: Busy, but not hassled
  • 3: Mildly angry, irritated, and hassled, but it does not show
  • 4: Moderately angry, so hassled shows in your voice
  • 5: Very angry, body tense, maybe fists clenched, ready to burst
  • 6: Furious, forced to show it physically, almost out of control
  • 7: Enraged, out of control, throwing objects, hurting self/others

• Risk for heart attack increases with the level and number of anger outbursts

• The Integrative and control centers are in the central nervous system (CNS)

• Communication between the CNS and the rest of the body is carried out by the peripheral nervous system (PNS)

• Communication lines between the CNS and the rest of the body are done by the cranial nerves and spinal nerves

• The PNS sensory (afferent) division conducts impulses from receptors to the CNS via somatic and visceral sensory nerve fibers

• The motor (efferent) division conducts impulses from the CNS to effectors (muscles and glands)

• The sympathetic division mobilizes body systems during activity ("fight or flight")

• The parasympathetic division conserves energy and promotes "housekeeping" functions during rest

• The autonomic nervous system (ANS) conducts impulses from the CNS to cardiac muscles, smooth muscles, and glands (visceral motor/involuntary)

• The somatic nervous system conducts impulses from the CNS to skeletal muscles (somatic motor/voluntary)

• Reactive aggression has a number of structures involved include the Threat Network, and Regulatory Condition

Key Cortical Areas

• Executive function

• Action planning & judgment

• Inhibition of behavioral impulses

• Regulation of emotions

• Processing sensory input

• Deriving meanings

• Connecting to memory

• Processing emotions

• Violence-prone persons have reduced prefrontal volume and activity

• Amygdala activation is sensitized to threat cues

• Those with ACC damage are less distressed by pain

• Neural circuitry underlying emotion regulation and behavior is complex

• The prefrontal cortex is responsible for executive functioning, decision-making, planning, representation of goals, and moderating social behavior/impulse control

• The anterior cingulate cortex (ACC) bridges attention, thought, action, and emotion, detects errors, monitors conflict, and registers pain, with activation associated with effortful emotion regulation

• The amygdala recruits/coordinates cortical arousal, providing vigilant attention to threat and processing aversive stimuli, and modulating aggressive behavior

• OFC has social information processing, regulates emotions, and restraining impulses

• Blair (2012) found orbital, medial, ventromedial frontal cortex implicated in the anger response

• Anger expression occurs when these regulatory regions are overwhelmed or compromised

• Lesions to ventromedial and ventrolateral frontal cortex are associated with difficulties in the regulation of anger, rage, and reactive aggression

Dorsal ACC

• Upper ACC, involved in reward-based decision making
• Monitors and controls cognitive-emotional processes
• Regulates aggressive behavior
• Left dorsal ACC activation occurs as anger is experienced, operating as a neural alarm system
• The limbic system involves homeostasis, emotional life and memories
• Amygdala decodes threat and emotion & does processing of trauma memories and strong emotion
• Predisposition to anger positively correlates with increased amygdala volume (Blair, 2012)
• "Top-down" control of the amygdala (AMY) arises from the anterior cingulate cortex (ACC) and ventral medial prefrontal cortex (vmPFC) which is important for moral behaviors
• "Bottom-up" modulation arises from the hypothalamus, regulating autonomic system reactions to social signals
• Hypothalamus is part of the limbic system and through connection to pituitary gland regulates various endocrine glands and organ functions
• Hippocampus consolidates of short- and long-term memory and spatial memory
• Hippocampal activation is associated with angry rumination, & causes increased encoding of the provocation in memory
• Dysfunctions in frontal cortex threat-regulatory systems increase anger
• Frustration of reward expectations is associated with anger
• Periaqueduct Grey primary control center for descending pain modulation, descents from midbrain & connects to the spine
• OFC processing social cues and can mediate pathways for anger-driven reactive aggression
• Phineas Gage had an accident that changed his personality and made him aggressive

"Neurobiology of Aggression and Violence" (Siever) Model:

• Top-down "brakes" include suppression/regulation via the orbital frontal cortex and the anterior cingulate gyrus, influenced by cultural/social factors
• Early information processing/cognitive appraisal involves sensory distortions (drugs, alcohol, metabolic disturbances), sensory deficits (hearing, vision loss), and cognitive impairment
• Bottom-up drive" involves signal/trigger from the amygdala and insula, influenced by developmental stress/trauma
• Borderline personality disorder involves instability via social relationships, self-image, and affects
• It involves marked impulsivity beginning in early adulthood
• Frantic efforts to avoid real abandonment
• Unstable relationships with alternation of idealization and devaluation
• Instability of self and identity
• Impulsive behavior such as spending, sex, substance abuse + more
• Suicidal behavior or self mutilation
• Affective instability of chronic emptiness
• Difficulty controlling anger
• Stress related paranoid ideation + dissociation