Question

Individuals experience various mood states or emotions at varying times every day, both subtle changes and obvious changes, that can result in attitude alternations with both negative and positive effects and impair or facilitate performance. The connections in the brain between emotion and memory have been particularly interesting to researchers given that neural networks that are activated by mood states are linked with neural networks that process basic perceptual functions such as word processing. Dr. Siebert has conducted a number of research experiments inducing various mood states through the use of music and then studying the effects of mood on lexical processing. (Dr. Pennie S. Siebert)

Previous research has shown that mood effects can be found in brain function at the level of lexical access. According to the associative network model of memory and emotion, emotions are represented in networks of nodes, as are words. Stimulation of emotion nodes activates networks that prime the retrieval of word nodes, creating mood-related effects on word retrieval such that positive emotions are associated with faster retrieval of positive words and negative moods are associated with faster retrieval of negative words. However, the speed of word retrieval may vary by type of mood, indicating stronger mood-related effects for some emotions compared to others. To assess differences in the speed of word retrieval under the influence of various mood states, researchers randomly assigned participants to happy, sad or neutral mood conditions and then tested their lexical retrieval of emotion-laden words.Participants were randomly assigned to listen to 30 minutes of happy, sad, or neutral music. They were then given a Reicher test which briefly presents a short string of letters that may or may not form a word. Participants were tasked with deciding whether or not the letters represented a word. Reaction time on the Reicher test was recorded for the three groups. Lower reaction time scores indicate greater mood effects on memory.

Research Question: Is there a difference in word recall among individuals who listen to happy, sad and neutral music?

Sad: 384.82, 380.26, 324.24, 314.68, 336.74, 380.26, 404.62, 331.46, 338.04, 418.28 [T=3613.98; M=361.40]

Neutral: 466.32, 430.94, 332.28, 338.04, 418.28, 597.08, 482.74, 436.74, 442.28, 580.34 [T=4525.04; M=452.50]   

Happy: 397.08, 482.74, 332.60, 397.92, 418.94, 519.54, 387.74, 442.62, 376.50, 360.34 [T=4116.08; M=411.61]

1. Write null and alternative hypotheses (in words and notation) appropriate for this research scenario.

2. Explain the concepts of SS_between, SS_within, SS_total, MS_between, and MS_within. With respect to this specific dataset, interpret what are those numbers are telling you?

3. Using the ANOVA Formula Worksheet, compute an ANOVA to test the hypotheses at an α = .05.

4. Compute the η² and interpret it. What might be variables that would influence mood other than listening to certain types of music?

Answer 1