Lecture 11: Stress and Police Memory

What is stress on a psycho-psychiological perspective?

Subjective experience of being overwhelmed, anxious or under pressure, although the intensity of stress may depend on cognitive appraisal, how an individual interprets the situation.

What is stress from a physiological level?

Acute stress is a biological response to a perceived threat or challenge, involving the activation of the Autonomic nervous system and the Hypothalamic-Pituitary-Adrenal Axis. Please note that physiological arousal does not always equal psychological stress.

How is stress represented from the fundamental memory field vs an eyewitness memory field?

Fundamental memory field → focuses on theoretical models and lab studies, with lab-validated stresses, findings are normally mixed in whether or not stress enhances or impairs memory.
Eyewitness memory → focus on real-world scenarios, and uses more ecologically valid stimuli, findings conclude that acute stress impairs memory.

What does fundamental memory research find about stress’s effects?

Suggests that acute stress during encoding can enhance recall memory especially when encoding and stress occurs within the same context.
However, stress before or during encoding impairs memory.

Describe the Easterbrook hypothesis?

Highly aroused witnesses have better memory for central details than peripheral details (“tunnel vision”)

What studies present with evidence for the easterbrook hypothesis?

Shields et al, 2017, → stress enhances memory for relevant information, but impairs memory for peripheral information
Pezdek & Reisberg, 2022 → stress may enhance central but often imparis peripheral details.
Yuille & Cutshall (field study → used real-life shooting with witnesses → found that that high stress doesn't always impair memory, especially for central details.
Valentine & Mesout (2009)– London Dungeon Study → found that higher state anxiety is linked to fewer correct descriptors and more incorrect details.

What is the weapon's focus effect?

Presence of a weapon during a crime draws attention away from other details • Fawcett et al (2013)
Meta-analysis of 47 studies. Moderate effect size.
Effect decreased with increasing retention interval and was greater for threatening than non-threatening scenarios.
However, was also an effect of unusualness

What were the differences between eyewitness and fundamental research?

How do they make participants stressed? → validated lab measures, vs. scenario baked stressors, lab measures normally invoke high physiological stress, to note is that these different levels of stress can influence memory differently
How do they know participants are stressed? —> eyewitness use self-reported stress levels, compared to measures in lab settings
How long do participants remember for? → the effect of stress can last for hours, therefore, as eyewitness studies use single session designs, they end up studying immediate recall but this does not reflect real-world conditions
What is being remembered? → memory for events experienced during stressor for eyewitness, very applicable

What is a flashblub memory?

a highly detailed, exceptionally vivid, and seemingly permanent memory of the circumstances surrounding learning about a surprising and emotionally significant event.

What is the Mandela Effect?

refers to a phenomenon where large groups of people remember an event or detail differently from how it actually occurred.

What does research around memory for traumatic events say about the effect of trauma on memory?

Some difficulties exist in analysing this as ground truth is unable to be determined

however Mckinnin et al, 2014, found that survivors of a plane emergency landing who developed PTSD were more likely to include irrelevant details compared to those who didn’t.

What is the effect of experience on a police officer’s stress response?

According to Baldwin et al, 2019, Experience and training did not consistently buffer stress responses.

What did field studies conclude on the effect of stress on memory in the police enforcement context?

Generally, field studies show that police enforcement officers are no immune to memory distortion, police officers showed the weapon focus effect, recall fewer correct details about a case when under higher stress and high activity and displayed the tunnel effect.

What did Murray et al, 2014 conclude about efficient scanners and inefficient scanners?

Efficient scanners

What was the effect of a Mnemonic device in increasing memory recall in Dun’s study?

It increased immediate and delayed recall, in a high stress situation.