Archery can be described as a static sport requiring strength and endurance of the upper body, in particular the shoulder girdle (Mann, 1984 / Mann &amp / Littke, 1989). To get a good record in an archery competition, one requires well-balanced and highly reproducible movements during the shooting (Nishizono, 1987). The bowstring is released when audible impetus is received from a device called &ldquo / clicker&rdquo / . As the fall of the clicker is an acoustic stimulus, it may evoke a sequence of potentials that can be recorded from the scalp of an archer. Auditory Evoked Potentials (AEPs) occur at different latencies and with various relations to the auditory stimuli. Therefore, the present study aims at investigating the Long-latency Auditory Evoked Potentials in Recurve Archery. Research questions can be stated briefly as follows: (1) What kind of Brain Potentials are Evoked by the Event (Fall of Clicker) during Archery Shooting? (2) Is there any significant difference between the characteristics of the potentials measured in laboratory conditions and during archery shooting? (3) Is there any significant difference between the successful and unsuccessful shots in terms of Auditory Evoked Brain Potentials? (4) Does Archery Shooting session have any effect on Auditory Evoked Brain Potentials? The subjects of the present study were 10 non-archers (N=6 males / N=4 females) for control trials and 15 archers (N=9 males / N=6 females) for archery shooting experiments. All subjects reported normal hearing, had medical histories free of significant neurological problems, and were not taking medication known to affect brain activity. Six different control paradigms have been created. Archery shootings were performed from 18 m that is official competition distance with target face.AEBPs were recorded 200 ms before and 800 ms after the trigger (fall of the clicker) over the vertex during the shots of each subject. Paradigm 1 and 5 was conducted just before and after the archery shooting to test the effect of archery shooting on AEBPs. The hit-area is defined as the rectangle between (x1, y1), (x1, y2), (x2, y1), (x2, y2) and the miss-area is the outer part of the hit-area on the target face. The preliminary analysis has shown that fall of the clicker evokes long latency auditory brain potentials with the latency of 100 msec and 200 msec. These responses are called as N1-P2 components. The means and standard deviations of both N100 and P200 amplitudes were as follows: N100 = 27,73 &plusmn / 16,82, P200 = -21,89 &plusmn / 20,46. The latencies of given brain responses were also summarized as: N100 = 141,93 &plusmn / 41,46 / P200 = 211,8 &plusmn / 43,97. N1 amplitude was significantly different in archery shooting than that of control conditions (p&lt / 0.05) except for trial 3, N1 latency was significantly different than that of trial 2 &ndash / 5 (p&lt / 0.05). P2 amplitude is significantly different in archery shooting than that of trial 6 (p&lt / 0.05). However, there was no significant difference in terms of P2 latency between archery shooting and control conditions (p&gt / 0.05). There was no significant difference between successful and unsuccessful shots in terms of N1-P2 components (p&gt / 0.05). An archery shooting session did not create any difference between these components recorded before and after the shot (p&gt / 0.05). Having higher N1 amplitudes during archery shooting can be explained by the known multi-component structure of this wave. Different lobes and regions of the brain can be active during the time of the scalp-recorded N1 and simultaneous involvement of several of these areas may be contributing to the electrical field recorded at scalp in the archery shooting paradigm.

Previous evidence has shown that older adults may have specific declines in prefrontal cortex (PFC)-mediated processes supported source memory retrieval, such as strategic retrieval and post-retrieval monitoring. This decline may manifest in the form of attenuated late-frontal ERP effects. Behavioral research suggests that explicitly integrating a target context, or source, with a stimulus during encoding will improve subsequent source memory performance for both younger and older adults. Explicit item-feature binding instructions during encoding may alleviate source memory impairments, in part, by reducing the need for strategic processing during episodic retrieval. The present ERP study investigated whether explicit direction of attention toward item-feature integration may reduce age-related deficits in source memory by alleviating the necessity of frontally-mediated strategic processing at retrieval. Results demonstrated that explicit direction of attention improved source memory accuracy for both young and older adults, but older adults benefited less than the young, indicating additional age-related deficits. ERPs revealed that explicit encoding support attenuated post-retrieval monitoring effects in the young. In the old, explicit encoding instruction resulted in earlier onset of early frontal effects, possibly related to familiarity. Results suggest explicit direction of attention toward item-source integration at encoding may improve source memory by alleviating the need for strategic retrieval, but age-related deficits persist.

Thesis (M. Sc.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (leaves 82-94). Also available via the World Wide Web.

Thesis (doctoral)--Universität Leipzig, 2001. / Includes bibliographical references (p. 141-159).

Typical depredation behavior by cetaceans involves stealing or damaging prey items already captured by recreational or commercial fishing gear. Depredation among cetaceans has been reported to be increasing in both severity and frequency globally. This behavior is of particular concern for small stocks of cetaceans since any interaction with fishing gear has the potential to injure or kill animals leading to unsustainable losses. In Florida, depredation became evident in 2006 when the number of bottlenose dolphin (Tursiops truncatus) strandings resulting from fishing gear ingestion or entanglement sharply increased. For the resident dolphin community in Sarasota Bay, modeling showed continued mortalities from recreational fishing gear interactions were not sustainable. The major goals of this study were to 1.) characterize depredation and recreational angler interactions involving dolphins in Sarasota Bay, 2.) reduce dolphin-angler interactions through outreach, 3.) examine a case study to investigate the link between dolphin hearing loss and angler interaction behavior, 4.) test the effectiveness of passive acoustics in monitoring dolphin depredation at a fishing pier. Findings from this study provided a better understanding of depredation and angler interactions. Results indicated that dolphin-angler interactions in Sarasota Bay are increasing in frequency and are affecting an increasing number of dolphins, specifically adult males. Some dolphins in Sarasota Bay appear to utilize depredation as a foraging method (not just an opportunistic behavior) and were significantly more likely to be within 50 m of an active fishing line. Depredation and angler interaction behavior appear to increase in times of prey depletion (such as during a red tide) and heightened angler fishing activity. Educational outreach using an informational card proved successful in a case study showing about a 30% reduction in dolphin provisioning rates. The case study of F201 offers preliminary evidence that hearing loss is linked to depredation behavior and death for wild dolphins. Also, by detecting echolocation clicks as a proxy for dolphin presence, passive acoustics showed potential as an inexpensive method for monitoring depredation in problematic areas. Conclusions from this study can be utilized by scientists and managers when assessing depredation rates for a cetacean community and implementing an action plan.

Purpose: To explore new methodologies to quantify binocular interactions and shed light on their possible neural generators. Methods: Binocular inhibition (BI) was experimentally produced in 40 visually healthy subjects by inserting a series of neutral density (ND) filters in front of one eye. Visual evoked potentials were recorded with stimuli tuned for check size, location and contrast. The Pulfrich effect was investigated using computerized pendulums. Results: Stimulus parameters required to generate maximal BI differ from those for maximal binocular summation (BS). The phase shift required to reverse the Pulfrich effect was proportional to the strength of the ND filter used, and the implicit time measured with VEPs and calculated with the PE correlate. Conclusion: It appears separate neural generators are responsible for BI and BS.

Cervical vestibular evoked myogenic potential (cVEMP) testing is widely used in the assessment of vestibular disorders in clinical practice (Welgampola & Colebatch, 2003). Ocular vestibular evoked myogenic potentials (oVEMPs) are similar to the cervical VEMPs in that the vestibular system is also stimulated by a loud sound. The difference is that the response is measured on the inferior oblique muscle of the eye as opposed to the sternocleidomastoid muscle (SCM) of the neck (Chihara, Iwasaki, Ushio, & Murofushi, 2007). The current study compares the standard cervical VEMP to the ocular VEMP in both control subjects and participants with “clinically certain” Ménière’s disease. By investigating cervical VEMPs in comparison to ocular VEMPs we aimed to improve the ability to stage and diagnose Ménière’s disease using the ocular VEMP. 22 control participants and 19 participants with confirmed unilateral Ménière’s disease took part in the study. The peak latency and amplitudes of the ocular and cervical VEMP tests were recorded and analysed. In addition, the background electromyographic (EMG) activity of both the inferior oblique and sternocleidomastoid muscles was recorded throughout testing. A questionnaire was also distributed to all participants to compare the relative difficulty of the VEMP tests. Statistical analysis using the paired t-test, standard t-test and the one-way ANOVA on ranks test was applied to determine a difference between the control and patient groups for both the ocular and cervical VEMP tests. Overall, the threshold and IAD ratio measures did not produce any significant results when sound was presented to the affected ear for the cervical and ocular VEMP tests. A significant reduction in amplitude of the VEMPs from the Ménière’s groups was found compared to the control groups for the ocular the cervical VEMPs. Overall, an increase in P2 and N3 latency of the ocular VEMP response in Ménière’s patients was determined. Results from the questionnaire suggest that the ocular VEMP test was more tolerable to the cervical VEMP test in this current study. Furthermore, statistical analyses revealed no significant differences in EMG level between the control and Ménière’s group for both the ocular and cervical VEMP data. Overall, results suggest that both the cervical and ocular VEMP tests provide information regarding the integrity of the saccule, owing to the abnormal VEMP findings in the participants with Ménière’s disease. In addition, this study provides evidence that the ocular VEMP is as useful a tool in diagnosing Ménière’s disease as the cervical VEMP.

Melanin is the dark pigment found in most organisms that gives color to the skin, hair, feathers, and eyes of vertebrates. While melanin is known to also be present in the stria vascularis of the mammalian cochlea, its function in the inner ear is still unknown. Some previous studies have indicated that melanin may serve to protect the mammalian ear from hearing loss. Minimal previous research on melanin within the inner ears of fishes has been conducted. In this study, the melanin levels in the inner ears of different color morphs of two fish species (Poecilia latipinna and Cyprinus carpio) were examined, as well as the potential protective role of melanin from acoustical stress. To identify the relationship between fish color morph and inner ear melanin, a spectrophotometric melanin assay was used for dissected inner ears, and transmission electron microscopy (TEM) was used to examine melanosome structure in the crus commune of the inner ears. For each color morph and species, hearing thresholds were quantified before and after sound exposure (150 Hz tone at 165 dB re 1 μPa for 48 h) by measuring auditory evoked potentials (AEPs). Melanin levels were associated with scale color, with black morphs having more inner ear melanin than white or golden morphs. TEM imaging showed that melanosome size varied among color morphs, with black P. latipinna morphs having larger melanosomes than white morphs. Hearing thresholds did not differ significantly among color morphs before sound exposure in either species. However, hearing thresholds post-sound exposure and the associated threshold shifts significantly differed between black morphs and other color morphs in the two species, with black morphs having lower thresholds and exhibiting less hearing loss than the other morphs. This suggests that melanin plays a protective role in the teleost inner ear, similar to what other researchers have found in mammalian models. Teleost fishes may be a new, more efficient model for testing melanin's function in the inner ear and how it interacts with stress from acoustical trauma and ototoxic drugs.

Cervical vestibular evoked myogenic potential (cVEMP) testing is widely used in the assessment of vestibular disorders in clinical practice (Welgampola & Colebatch, 2003). Ocular vestibular evoked myogenic potentials (oVEMPs) are similar to the cervical VEMPs in that the vestibular system is also stimulated by a loud sound. The difference is that the response is measured on the inferior oblique muscle of the eye as opposed to the sternocleidomastoid muscle (SCM) of the neck (Chihara, Iwasaki, Ushio, & Murofushi, 2007). The current study compares the standard cervical VEMP to the ocular VEMP in both control subjects and participants with “clinically certain” Ménière’s disease. By investigating cervical VEMPs in comparison to ocular VEMPs we aimed to improve the ability to stage and diagnose Ménière’s disease using the ocular VEMP. 22 control participants and 19 participants with confirmed unilateral Ménière’s disease took part in the study. The peak latency and amplitudes of the ocular and cervical VEMP tests were recorded and analysed. In addition, the background electromyographic (EMG) activity of both the inferior oblique and sternocleidomastoid muscles was recorded throughout testing. A questionnaire was also distributed to all participants to compare the relative difficulty of the VEMP tests. Statistical analysis using the paired t-test, standard t-test and the one-way ANOVA on ranks test was applied to determine a difference between the control and patient groups for both the ocular and cervical VEMP tests. Overall, the threshold and IAD ratio measures did not produce any significant results when sound was presented to the affected ear for the cervical and ocular VEMP tests. A significant reduction in amplitude of the VEMPs from the Ménière’s groups was found compared to the control groups for the ocular the cervical VEMPs. Overall, an increase in P2 and N3 latency of the ocular VEMP response in Ménière’s patients was determined. Results from the questionnaire suggest that the ocular VEMP test was more tolerable to the cervical VEMP test in this current study. Furthermore, statistical analyses revealed no significant differences in EMG level between the control and Ménière’s group for both the ocular and cervical VEMP data. Overall, results suggest that both the cervical and ocular VEMP tests provide information regarding the integrity of the saccule, owing to the abnormal VEMP findings in the participants with Ménière’s disease. In addition, this study provides evidence that the ocular VEMP is as useful a tool in diagnosing Ménière’s disease as the cervical VEMP.

Thesis (Ph. D.)--Ohio University, June, 1991. / Title from PDF t.p.