Limits...
Functional and structural brain modifications induced by oculomotor training in patients with age-related macular degeneration.

Rosengarth K, Keck I, Brandl-Rühle S, Frolo J, Hufendiek K, Greenlee MW, Plank T - Front Psychol (2013)

Bottom Line: Despite substantial variability in the training effects, on average, AMD patients benefited from the training measurements as indexed by significant improvements in their fixation stability, visual acuity, and reading speed.We also found a significant increase in gray and white matter in the posterior cerebellum after training in the patient group.Our results show that functional and structural brain changes can be associated, at least on the short-term, with benefits of oculomotor and/or reading training in patients with central scotomata resulting from AMD.

View Article: PubMed Central - PubMed

Affiliation: Institute for Experimental Psychology, University of Regensburg Regensburg, Germany.

ABSTRACT
Patients with age-related macular degeneration (AMD) are reliant on their peripheral visual field. Oculomotor training can help them to find the best area on intact peripheral retina and to efficiently stabilize eccentric fixation. In this study, nine patients with AMD were trained over a period of 6 months using oculomotor training protocols to improve fixation stability. They were followed over an additional period of 6 months, where they completed an auditory memory training as a sham training. In this cross-over design five patients started with the sham training and four with the oculomotor training. Seven healthy age-matched subjects, who did not take part in any training procedure, served as controls. During the 6 months of training the AMD subjects and the control group took part in three functional and structural magnetic resonance imaging (MRI) sessions to assess training-related changes in the brain function and structure. The sham-training phase was accompanied by two more fMRI measurements, resulting in five MRI sessions at intervals of 3 months for all participants. Despite substantial variability in the training effects, on average, AMD patients benefited from the training measurements as indexed by significant improvements in their fixation stability, visual acuity, and reading speed. The patients showed a significant positive correlation between brain activation changes and improvements in fixation stability in the visual cortex during training. These correlations were less pronounced on the long-term after training had ceased. We also found a significant increase in gray and white matter in the posterior cerebellum after training in the patient group. Our results show that functional and structural brain changes can be associated, at least on the short-term, with benefits of oculomotor and/or reading training in patients with central scotomata resulting from AMD.

No MeSH data available.


Related in: MedlinePlus

Fixation stability (% fixation around 2 degrees of target) and reading speedfor the successive measurements periods depicted for individual patients (symbols, connected by dotted lines) and group means (colored lines). The results show improved fixation stability after training (significant main effect of session p = 0.01). Pairwise comparisons show a significant increase in fixation stability after on average 3 months of training (p = 0.04). The memory training has no effect on fixation stability regardless of whether memory training was performed before (memory first p = 0.29) or after fixation training (memory after p = 0.93), ruling out non-specific placebo effects. A similar pattern can be observed for the reading speed. Reading speed increases over the 6 months of training (significant main effect of session p = 0.02). Auditory memory training had no effect on reading speed regardless of whether memory training was performed before (memory first p = 0.41) or after fixation training (memory after p = 0.57).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3713239&req=5

Figure 4: Fixation stability (% fixation around 2 degrees of target) and reading speedfor the successive measurements periods depicted for individual patients (symbols, connected by dotted lines) and group means (colored lines). The results show improved fixation stability after training (significant main effect of session p = 0.01). Pairwise comparisons show a significant increase in fixation stability after on average 3 months of training (p = 0.04). The memory training has no effect on fixation stability regardless of whether memory training was performed before (memory first p = 0.29) or after fixation training (memory after p = 0.93), ruling out non-specific placebo effects. A similar pattern can be observed for the reading speed. Reading speed increases over the 6 months of training (significant main effect of session p = 0.02). Auditory memory training had no effect on reading speed regardless of whether memory training was performed before (memory first p = 0.41) or after fixation training (memory after p = 0.57).

Mentions: Changes in fixation stability were assessed with the Nidek MP-1 microperimeter (Nidek Co, Japan) as described in the methods section. Figure 3 shows an example of the development of fixation stability in one patient (AMD2) from before training, after 3 months training and after 6 months training. The left and middle columns show the distribution of fixation samples around the target, with the middle column additionally giving percentages of fixation samples falling in a range of 2° or 4° diameter visual angle around the target. We used the percentages of fixation points that fell in a range of 2° diameter visual angle around the center of the target as measure for fixation stability, in this patient (AMD2) increasing from 43% before training to 100% after training. The right column in Figure 3 gives the respective time profile of the first 10 s of fixation, which also improved substantially for patient AMD2 over the training period of 6 months. Figure 4 gives an overview of the mean development in fixation stability for all nine AMD patients. To assess immediate training effects of the eccentric viewing training, fixation stability data in Figure 4 was pooled across the group that started with the auditory memory training and the group that started with the eccentric viewing training for the three sessions immediately “before training,” “during training,” and “after training” (n = 9), with the session “during training” and “after training” on average 3 months or 6 months after the start of the training, respectively. AMD5 had an additional measurement of fixation stability 7 weeks after the start of the oculomotor training (fixation stability of 82% within 2° degrees around target), not shown in Figure 4. The two remaining sessions, in which both groups completed the auditory memory training, were analysed separately for the group that started with the auditory memory training (sessions “memory before 1” and “memory before 2”; n = 5) and for the group who did the auditory memory training after the eccentric viewing training (sessions “memory after 1” and “memory after 2”; n = 4, patient AMD9 has, at the time of submission, not yet completed the last session “memory after 2”).


Functional and structural brain modifications induced by oculomotor training in patients with age-related macular degeneration.

Rosengarth K, Keck I, Brandl-Rühle S, Frolo J, Hufendiek K, Greenlee MW, Plank T - Front Psychol (2013)

Fixation stability (% fixation around 2 degrees of target) and reading speedfor the successive measurements periods depicted for individual patients (symbols, connected by dotted lines) and group means (colored lines). The results show improved fixation stability after training (significant main effect of session p = 0.01). Pairwise comparisons show a significant increase in fixation stability after on average 3 months of training (p = 0.04). The memory training has no effect on fixation stability regardless of whether memory training was performed before (memory first p = 0.29) or after fixation training (memory after p = 0.93), ruling out non-specific placebo effects. A similar pattern can be observed for the reading speed. Reading speed increases over the 6 months of training (significant main effect of session p = 0.02). Auditory memory training had no effect on reading speed regardless of whether memory training was performed before (memory first p = 0.41) or after fixation training (memory after p = 0.57).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3713239&req=5

Figure 4: Fixation stability (% fixation around 2 degrees of target) and reading speedfor the successive measurements periods depicted for individual patients (symbols, connected by dotted lines) and group means (colored lines). The results show improved fixation stability after training (significant main effect of session p = 0.01). Pairwise comparisons show a significant increase in fixation stability after on average 3 months of training (p = 0.04). The memory training has no effect on fixation stability regardless of whether memory training was performed before (memory first p = 0.29) or after fixation training (memory after p = 0.93), ruling out non-specific placebo effects. A similar pattern can be observed for the reading speed. Reading speed increases over the 6 months of training (significant main effect of session p = 0.02). Auditory memory training had no effect on reading speed regardless of whether memory training was performed before (memory first p = 0.41) or after fixation training (memory after p = 0.57).
Mentions: Changes in fixation stability were assessed with the Nidek MP-1 microperimeter (Nidek Co, Japan) as described in the methods section. Figure 3 shows an example of the development of fixation stability in one patient (AMD2) from before training, after 3 months training and after 6 months training. The left and middle columns show the distribution of fixation samples around the target, with the middle column additionally giving percentages of fixation samples falling in a range of 2° or 4° diameter visual angle around the target. We used the percentages of fixation points that fell in a range of 2° diameter visual angle around the center of the target as measure for fixation stability, in this patient (AMD2) increasing from 43% before training to 100% after training. The right column in Figure 3 gives the respective time profile of the first 10 s of fixation, which also improved substantially for patient AMD2 over the training period of 6 months. Figure 4 gives an overview of the mean development in fixation stability for all nine AMD patients. To assess immediate training effects of the eccentric viewing training, fixation stability data in Figure 4 was pooled across the group that started with the auditory memory training and the group that started with the eccentric viewing training for the three sessions immediately “before training,” “during training,” and “after training” (n = 9), with the session “during training” and “after training” on average 3 months or 6 months after the start of the training, respectively. AMD5 had an additional measurement of fixation stability 7 weeks after the start of the oculomotor training (fixation stability of 82% within 2° degrees around target), not shown in Figure 4. The two remaining sessions, in which both groups completed the auditory memory training, were analysed separately for the group that started with the auditory memory training (sessions “memory before 1” and “memory before 2”; n = 5) and for the group who did the auditory memory training after the eccentric viewing training (sessions “memory after 1” and “memory after 2”; n = 4, patient AMD9 has, at the time of submission, not yet completed the last session “memory after 2”).

Bottom Line: Despite substantial variability in the training effects, on average, AMD patients benefited from the training measurements as indexed by significant improvements in their fixation stability, visual acuity, and reading speed.We also found a significant increase in gray and white matter in the posterior cerebellum after training in the patient group.Our results show that functional and structural brain changes can be associated, at least on the short-term, with benefits of oculomotor and/or reading training in patients with central scotomata resulting from AMD.

View Article: PubMed Central - PubMed

Affiliation: Institute for Experimental Psychology, University of Regensburg Regensburg, Germany.

ABSTRACT
Patients with age-related macular degeneration (AMD) are reliant on their peripheral visual field. Oculomotor training can help them to find the best area on intact peripheral retina and to efficiently stabilize eccentric fixation. In this study, nine patients with AMD were trained over a period of 6 months using oculomotor training protocols to improve fixation stability. They were followed over an additional period of 6 months, where they completed an auditory memory training as a sham training. In this cross-over design five patients started with the sham training and four with the oculomotor training. Seven healthy age-matched subjects, who did not take part in any training procedure, served as controls. During the 6 months of training the AMD subjects and the control group took part in three functional and structural magnetic resonance imaging (MRI) sessions to assess training-related changes in the brain function and structure. The sham-training phase was accompanied by two more fMRI measurements, resulting in five MRI sessions at intervals of 3 months for all participants. Despite substantial variability in the training effects, on average, AMD patients benefited from the training measurements as indexed by significant improvements in their fixation stability, visual acuity, and reading speed. The patients showed a significant positive correlation between brain activation changes and improvements in fixation stability in the visual cortex during training. These correlations were less pronounced on the long-term after training had ceased. We also found a significant increase in gray and white matter in the posterior cerebellum after training in the patient group. Our results show that functional and structural brain changes can be associated, at least on the short-term, with benefits of oculomotor and/or reading training in patients with central scotomata resulting from AMD.

No MeSH data available.


Related in: MedlinePlus