BDNF Val66Met polymorphism and goal-directed behavior in healthy elderly — evidence from auditory distraction

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Abstract

Aging affects the ability to focus attention on a given task and to ignore distractors. 

These functions subserve response control processes for which fronto-striatal networks have been shown to play an important role. 

Within these networks, the brain-derived-neurotrophic-factor (BDNF), which is known to underlie aging effects, plays a pivotal role. 

We investigated how cognitive subprocesses constituting a cycle of distraction, orientation and refocusing of attention are affected by the functional BDNF Val66Met polymorphism using event-related potentials (ERPs) in 122 healthy elderly. 

Using an auditory distraction paradigm we found that the Val/Val genotype confers a disadvantage to its carriers. 

This disadvantage was partly compensated by intensified attentional shifting mechanisms. 

It could be based on response selection processes being more vulnerable against interference from distractors in this genotype group. 

Processes reflecting transient sensory memory processes, or the re-orientation of attention were not affected by the BDNF Val66Met polymorphism, suggesting a higher importance of BDNF for mechanisms related to response control, than stimulus processing. 

The results add on recent literature showing that the Met allele confers some benefit to its carriers. 

We suggest an account for unifying different results of BDNF Val66Met association studies in executive functions, based on the role of BDNF in fronto-striatal circuits.

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Highlights

► Variations in BDNF Val66Met polymorphism modulate goal-directed behavior. ► The Val/Val genotype confers a disadvantage in elderly. ► This disadvantage can partly be compensated by attentional shifting mechanisms. ► BDNF modulates distinct subprocesses within a distraction and re-focusing cycle.

Keywords

• Sensory processing;
• Auditory perception;
• EEG;
• BDNF Val66Met polymorphism;
• Healthy elderly

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Corresponding author at: Leibniz Research Centre for Working Environment and Human Factors, Ardeystraße 67, D-44139 Dortmund, Germany. Fax: + 49 231 1084 401.

• Stephan Getzmann^{a, ,} ,
• Patrick D. Gajewski^a,
• Jan G. Hengstler^a,
• Michael Falkenstein^a,
• Christian Beste^b

• ^a Leibniz Research Centre for Working Environment and Human Factors at the Technical University of Dortmund (IfADo), Germany
• ^b Institute for Cognitive Neuroscience, Biopsychology, Ruhr-University Bochum, Germany

•  
• Fuente: http://dx.doi.org/10.1016/j.neuroimage.2012.08.079, 

 

Assessment of cochlear and auditory pathways in patients with migraine

Authors

• Sherifa Ahmad Hamed, MD^{a, ,} ,
• Ahmed Hamdy Youssef, MD^a,
• Amal Mohammad Elattar, MD^b

• ^a Department of Neurology and Psychiatry, Assiut University Hospital, Assiut, Egypt
• ^b Department of Ear, Nose and Throat, Audiology Unit, Assiut University Hospital, Assiut, Egypt

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Abstract

Purpose

In this study, we aimed to determine the function of the cochlea and peripheral and central auditory pathways with migraine.

Materials and methods

Fifty-eight patients with migraine and 40 healthy subjects were assessed using routine diagnostic audiometry along with transient evoked otoacoustic emissions (TOAEs), distortion product otoacoustic emissions (DPOAEs), and auditory brainstem response (ABR) at high and low repetition rate frequencies.

Results

Nearly two thirds of patients with migraine had one or more abnormalities in electrophysiological testing. Compared with control subjects, patients reported significant lowering of TOAEs amplitude at frequencies of 1 kHz (right: P = .0003; left: P = .002), 3 kHz (right: P = .025), and 4 kHz (right: P = .019); prolonged wave III latency (right: P = .009); and I-V interpeak latency (IPL) (left: P = .024) at high repetition rate frequencies. Significant correlations were identified between age, duration of illness and frequency of migraine and TOAEs total response and at amplitude of 4 kHz, amplitudes of DPOAEs at 1, 1.5, 2, 3, and 5 kHz and I, III and wave latencies and I-V IPL of ABR at high rate frequencies.

Conclusions

These data suggest that subclinical changes in cochlear function and auditory pathways are associated with chronic migraine. It is possible that migraine could be accompanied by compromise of blood supply of auditory system.

Fuente:

American Journal of Otolaryngology

Volume 33, Issue 4, July–August 2012, Pages 385–394

Fuente de la imagen:  http://www.google.com.ar/imgres?hl=es&biw=1280&bih=612&tbm=isch&tbnid=D0qQux4gGQmZ2M:&imgrefurl=http://thenpmom.wordpress.com/2012/04/24/migraine-headaches-just-another-headache/&docid=4VMUYEPgoOMXMM&imgurl=http://thenpmom.files.wordpress.com/2012/04/migrainesufferer.jpg&w=900&h=542&ei=eXPvT57kGYyK8QTnp92jDQ&zoom=1

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