As a mental health professional with a background in trauma and posttraumatic stress disorder (PTSD), I can provide a detailed explanation of the exaggerated startle response in the context of combat-related PTSD.
Exaggerated startle response is a common symptom of PTSD, particularly among combat veterans. It is a part of the hyperarousal symptom cluster, which also includes insomnia, irritability, and difficulty concentrating. Hyperarousal refers to a state of heightened physiological and emotional reactivity to perceived threats. This heightened state can lead to an overreaction to stimuli that would not typically elicit such a strong response in someone without PTSD.
The startle response is a natural, automatic reaction to a sudden, unexpected stimulus. It is a protective mechanism that prepares the body to react to potential danger. In a healthy individual, the startle response is usually brief and subsides quickly. However, in individuals with PTSD, the startle response can be significantly amplified and prolonged.
There are several factors that contribute to the development of an exaggerated startle response in PTSD:

1. Trauma Exposure: The experience of traumatic events, such as combat, can lead to a heightened sense of vulnerability and a constant state of alertness. This can make individuals more sensitive to sudden stimuli and more likely to react with a startle response.

2. Neurochemical Changes: PTSD is associated with alterations in the brain's neurochemistry, particularly involving neurotransmitters like serotonin and norepinephrine. These changes can affect the way the brain processes sensory input and can contribute to an exaggerated startle response.

3. Fear Conditioning: During traumatic events, certain stimuli may become associated with the trauma through a process called fear conditioning. As a result, these stimuli can trigger an exaggerated startle response even when they are no longer associated with actual danger.

4. Hypervigilance: Individuals with PTSD often exhibit hypervigilance, which is a state of increased awareness and scanning of the environment for potential threats. This heightened state of alertness can make them more prone to experiencing exaggerated startle responses.

5. Sleep Disturbances: Sleep problems, such as insomnia and nightmares, are common in PTSD and can exacerbate the startle response. Poor sleep quality can lead to a state of heightened arousal and make individuals more sensitive to sudden stimuli.
The exaggerated startle response can have significant impacts on an individual's daily functioning. It can lead to social isolation, as individuals may avoid situations where they might be startled. It can also contribute to relationship problems, as loved ones may not understand the intensity of the reaction. Additionally, it can interfere with work and other responsibilities, as the constant state of alertness can be mentally and physically exhausting.
Treatment for PTSD often includes a combination of psychotherapy and medication. Cognitive-behavioral therapy (CBT), particularly trauma-focused CBT, can be effective in reducing the startle response by helping individuals to reprocess traumatic memories and develop more adaptive coping strategies. Medications, such as selective serotonin reuptake inhibitors (SSRIs), can also be used to target the neurochemical changes associated with PTSD and may help to reduce the startle response.
In conclusion, the exaggerated startle response is a complex symptom of PTSD that is influenced by a variety of factors, including trauma exposure, neurochemical changes, fear conditioning, hypervigilance, and sleep disturbances. Treatment for this symptom typically involves a combination of psychotherapy and medication to address the underlying causes and improve daily functioning.
read more >>

Combat PTSD Symptom: The Exaggerated Startle Response. Monday, November 17 2014 Harry Croft, M.D. A few weeks ago, I discussed how hyperarousal (or feeling --keyed up--) is a symptom area of combat posttraumatic stress disorder (PTSD). A symptom that is part of hyperarousal is an exaggerated startle response.Nov 17, 2014read more >>