title: Targeted memory reactivation, errors, and sleep-dependent memory consolidation: Implications for off-line motor learning

authors: Jahnke, Tyler Jovarn

subjects: Sleep

abstract: Memory consolidation benefits from sleep and is fundamental for motor learning. However, sleep-dependent consolidation occurs for a range of motor memories, some of which may be associated with successful practice trials and some of which may be associated with unsuccessful practice trials, or errors. Consequently, the aim of this thesis was to investigate whether it is possible to enhance sleep-dependent consolidation rates by constraining the learning environment in order to regulate errors during practice.

Chapter 1 reviews literature relevant to this question. Chapter Two presents an experiment in which we investigated whether sleep-dependent consolidation is likely to result in a higher rate of learning when many successful trials occur at the end of practice compared to when many unsuccessful practice trials occur at the end of practice. Results showed that the Successful-trials group displayed significant improvements in performance following a night of sleep, whereas the Unsuccessful-trials group did not. We concluded that sleep resulted in better learning in the successful trials group than the unsuccessful trials group because memories of more successful trials and fewer unsuccessful trials consolidated. A serial-position effect may explain these findings; however, more work is needed.

Chapter Three presents a follow-up experiment in which we used the same apparatus and protocol as in Chapter Two. However, we incorporated targeted memory reactivation to promote greater off-line consolidation of successful trials in the successful trials group, and of unsuccessful trials in the unsuccessful trials group. Results showed that both groups displayed significant improvements in performance following a night of sleep. We concluded that targeted memory reactivation may have augmented consolidation of successful trials at the expense of unsuccessful trials, but more work is necessary. The role of dopamine in memory consolidation was discussed.

The results of this thesis provide some support for the premise that it is possible to enhance sleep-dependent consolidation rates by constraining the learning environment in order to regulate errors during practice. Theoretical and practical implications of the findings are discussed in Chapter Four.

text: Targeted memory reactivation, errors, and sleep-dependent memory consolidation: Implications for off-line motor learning Memory consolidation benefits from sleep and is fundamental for motor learning. However, sleep-dependent consolidation occurs for a range of motor memories, some of which may be associated with successful practice trials and some of which may be associated with unsuccessful practice trials, or errors. Consequently, the aim of this thesis was to investigate whether it is possible to enhance sleep-dependent consolidation rates by constraining the learning environment in order to regulate errors during practice.

Chapter 1 reviews literature relevant to this question. Chapter Two presents an experiment in which we investigated whether sleep-dependent consolidation is likely to result in a higher rate of learning when many successful trials occur at the end of practice compared to when many unsuccessful practice trials occur at the end of practice. Results showed that the Successful-trials group displayed significant improvements in performance following a night of sleep, whereas the Unsuccessful-trials group did not. We concluded that sleep resulted in better learning in the successful trials group than the unsuccessful trials group because memories of more successful trials and fewer unsuccessful trials consolidated. A serial-position effect may explain these findings; however, more work is needed.

Chapter Three presents a follow-up experiment in which we used the same apparatus and protocol as in Chapter Two. However, we incorporated targeted memory reactivation to promote greater off-line consolidation of successful trials in the successful trials group, and of unsuccessful trials in the unsuccessful trials group. Results showed that both groups displayed significant improvements in performance following a night of sleep. We concluded that targeted memory reactivation may have augmented consolidation of successful trials at the expense of unsuccessful trials, but more work is necessary. The role of dopamine in memory consolidation was discussed.

The results of this thesis provide some support for the premise that it is possible to enhance sleep-dependent consolidation rates by constraining the learning environment in order to regulate errors during practice. Theoretical and practical implications of the findings are discussed in Chapter Four.

year: 2022

title: China's energy economy: Technical change, factor demand and interfactor/interfuel substitution

authors: Ma, Hengyun

subjects: China

abstract: With its rapid economic growth, China's primary energy consumption has exceeded domestic energy production since 1994, leading to a substantial expansion in energy imports, particularly of oil. China's energy demand has an increasingly significant impact on global energy markets. In this paper Allen partial elasticities of factor and energy substitution, and price elasticities of energy demand, are calculated for China using a two-stage translog cost function approach. The results suggest that energy is substitutable with both capital and labor. Coal is significantly substitutable with electricity and complementary with diesel while gasoline and electricity are substitutable with diesel. China's energy intensity is increasing during the study period (1995–2004) and the major driver appears to be due to the increased use of energy-intensive technology.

text: China's energy economy: Technical change, factor demand and interfactor/interfuel substitution With its rapid economic growth, China's primary energy consumption has exceeded domestic energy production since 1994, leading to a substantial expansion in energy imports, particularly of oil. China's energy demand has an increasingly significant impact on global energy markets. In this paper Allen partial elasticities of factor and energy substitution, and price elasticities of energy demand, are calculated for China using a two-stage translog cost function approach. The results suggest that energy is substitutable with both capital and labor. Coal is significantly substitutable with electricity and complementary with diesel while gasoline and electricity are substitutable with diesel. China's energy intensity is increasing during the study period (1995–2004) and the major driver appears to be due to the increased use of energy-intensive technology.

year: 2008

title: The development of guidelines for indigenous research ethics in Aotearoa/New Zealand.

authors: Hudson, Maui

abstract: The development of Indigenous frameworks for research ethics has been a key component of progressing Indigenous aspirations for research around the world. They have provided a focal point for challenging approaches to research that prioritise non-Indigenous methods and values, and allow non-Indigenous researchers to claim expert status over Indigenous peoples, places and knowledges. The theme of self-determination underpins contemporary approaches to Indigenous development and the repositioning of state-Indigenous nation relationships. This paper describes the background, development, and implementation by Māori communities and researchers of an Indigenous ethical framework in Aotearoa/New Zealand.

text: The development of guidelines for indigenous research ethics in Aotearoa/New Zealand. The development of Indigenous frameworks for research ethics has been a key component of progressing Indigenous aspirations for research around the world. They have provided a focal point for challenging approaches to research that prioritise non-Indigenous methods and values, and allow non-Indigenous researchers to claim expert status over Indigenous peoples, places and knowledges. The theme of self-determination underpins contemporary approaches to Indigenous development and the repositioning of state-Indigenous nation relationships. This paper describes the background, development, and implementation by Māori communities and researchers of an Indigenous ethical framework in Aotearoa/New Zealand.

year: 2016