ion. Talasli also found that there is an activation intensity factor which induced proactive inhibition and induced subjects to spend longer times studying the words, but resulted in a decreased ability to recall the words. The conclusions from this experiment were that PI may be due to the combined effects of inter- and intra-trial activation.
Morrow and Ryan (2002) presented the first normative data on PI using large numbers of test subjects (350), aged from 18 to 65, and stratified for education level and across age bands, using the Four-Word-Short-Term-Memory-Test (FWSTMT). Age and education were correlated with performance, and the researchers found a higher variance in performance relative to education in comparison to age. They suggest that higher education may be associated with a larger semantic network, which could increase performance on such tasks. They suggest the FWSTMT may be useful in clinical settings to detect deterioration in assessing the capacity for central information processing.
A series of experiments by Nairne, Whiteman and Kelley (1999) looked at the retention of word order using a range of retention intervals, but in which interference from prior trials was minimized. They attempted to minimize PI by changing the items on each trial. Results showed a decrease in order retention over increased retention times, and a build up of PI when items were repeated from trial to trail, which is consistent with other findings. A decline in retention was seen even in only a 2 sec delay, suggesting rapid decline in short-term memory. The experiments also showed considerable variability in rates of loss of recall, confounded by distractor tasks.
The release from proactive inhibition is usually found when the semantic category of word lists is changed. Wickens (1970) looked at various factors which can influence PI release in the brown-Peterson task by looking at the dimensions along which words are en...