Dysfunction in FHD is widespread in both complexity and hand networks, and impairments are demonstrated even when performing tasks that do not evoke dystonic symptoms. These results suggest that such impairments are inherent to, rather than symptomatic of, the disorder.

A growing body of literature has explored the influence of physical activity on brain structure and function. While the mechanisms of this relationship remain largely speculative, recent research suggests that one of the effects of physical exercise is an increase in synaptic long-term potentiation (LTP). This has not yet been explored directly in humans due to the difficulty of measuring LTP non-invasively. However, we have previously established that LTP-like changes in visual-evoked potentials (VEPs) can be measured in humans. Here, we investigated whether physical fitness status affects the degree of visual sensory LTP. Using a self-report measure of physical activity, participants were split into two groups: a high-activity group, and a low-activity group. LTP was measured and compared between the two groups using the previously established electroencephalography-LTP paradigm, which assesses the degree to which the N1b component of the VEP elicited by a sine grating is potentiated (enhanced) following a rapid "tetanic" presentation of that grating. Both groups demonstrated increased negativity in the amplitude of the N1b component of the VEP immediately after presentation of the visual "tetanus," indicating potentiation. However, after a 30-min rest period, the N1b for the high-activity group remained potentiated while the N1b for the low-activity group returned to baseline. This study presents the first evidence for the impact of self-reported levels of physical activity on LTP in humans, and sheds light on potential neurological mechanisms underlying the relationship between physical fitness and cognition.

Investigating the neural substrates of auditory processing of absolute pitch musicians has relevance for understanding the capabilities of the human brain for plasticity. Electroencephalography was used to examine the N1 of auditory-evoked potentials from absolute pitch musicians, nonabsolute pitch musicians, and nonmusicians during tone labeling tasks with and without presentation of a reference tone. Source localization using low-resolution electromagnetic tomography revealed that when labeling tones without a reference, absolute pitch musicians generated greater activity than nonabsolute pitch musicians in the left and right hemispheres. This suggests that when required to label tones without an external reference, absolute pitch musicians have the ability to recruit a greater network than nonabsolute pitch musicians or nonmusicians.

Background : Long-term potentiation (LTP) is recognised as a core neuronal process underlying long-term memory. However, a direct relationship between LTP and human memory performance is yet to be demonstrated. The first aim of the current study was thus to assess the relationship between LTP and human long-term memory performance. With this also comes an opportunity to explore factors thought to mediate the relationship between LTP and long-term memory. The second aim of the current study was to explore the relationship between LTP and memory in groups differing with respect to brain-derived neurotrophic factor (BDNF) Val 66 Met; a single-nucleotide polymorphism (SNP) implicated in memory function. Methods : Participants were split into three genotype groups (Val/Val, Val/Met, Met/Met) and were presented with both an EEG paradigm for inducing LTP- like enhancements of the visually-evoked response, and a test of visual memory. Results : The magnitude of LTP 40 min after induction was predictive of long-term memory performance. Additionally, the BDNF Met allele was associated with both reduced LTP and reduced memory performance. Conclusions : The current study not only presents the first evidence for a relationship between sensory LTP and human memory performance, but also demonstrates how targeting this relationship can provide insight into factors implicated in variation in human memory performance. It is anticipated that this will be of utility to future clinical studies of disrupted memory function.