The Stroop test as an experimental stressor

The Stroop test can be used as an experimental stressor to assess changes in the cardiovascular system. The ability of the human body to adapt to the external environment has been essential to our survival. During mental stress a range of cardiovascular responses are seen: vasodilation to skin and skeletal muscle, and increases in heart rate, cardiac output, and blood pressure. These changes are thought to reflect an increase in sympathetic nervous activity, and a decrease in parasympathetic nervous activity.

The Stroop test can be used in lab practicals to induce physiological stress in human volunteers. In today’s experiment  you replicated a shorten version of the  Stroop’s 1935 experiment, and recorded physiological measures of the stress response, heart rate and skin temperature.

Hypothesis

Our hypothesis was: “Performing a Stroop test will activate the stress responses  in volunteers”.

Based on this hypothesis, we expected to see an increase in heart rate and a decrease in skin temperature in volunteers.

Experimental set up

We used the Lt platform to record the volunteers’ reaction time (time/words), accuracy (number of errors), heart rate and peripheral skin temperature under 4 conditions:

Control conditions: 

Monochrome: read the words of colours written in black (for example, green, red, brown, blue, purple).

Rectangles: name the colour of each rectangle (for example, purple, blue, brown, red, green).

Experimental conditions:

Words: read the words that are written in a different colour (for example, purple, brown, green, red, blue).

Colours: name the colour that the word is written in (for example, green, red, blue, brown, purple).