Behavioural and electrophysiological studies of taste discrimination by the maxillary palps of larvae of Locusta migratoria (L.)

1975 ◽  
Vol 62 (3) ◽  
pp. 555-569
Author(s):  
W. M. Blaney
Keyword(s):  
Statistical Tests ◽  
Locusta Migratoria ◽  
Frequency Of Occurrence ◽  
Adequate Number ◽  
Electrophysiological Tests ◽  
Electrophysiological Studies ◽  
Taste Discrimination ◽  
Fibre Analysis ◽  
Plant Sources ◽  
Maxillary Palps

1. Behavioural studies show that larvae of Locusta migratoria (L.) can discriminate between certain simple chemicals and between chemicals obtained from plant sources. 2. Electrophysiological tests show that within each sensillum the same neurones respond to different chemicals. 3. The frequency of occurrence of sensilla with enhanced specificity to certain chemicals is investigated. 4. Statistical tests confirm that, despite the variability of response, across-fibre analysis could allow discrimination between chemicals provided an adequate number of senilla are used. 5. The conclusions are discussed in relation to current theories of chemoreceptor functioning.

The Control of Changes in Peripheral Sensilla Associated with Feeding in Locusta Migratoria (L.)

1972 ◽  
Vol 57 (3) ◽  
pp. 755-763
Author(s):  
E. A. BERNAYS ◽  
R. F. CHAPMAN
Keyword(s):  
Normal Level ◽  
Electrical Resistance ◽  
Locusta Migratoria ◽  
Corpus Cardiacum ◽  
Corpora Cardiaca ◽  
Diuretic Hormone ◽  
Stretch Receptors ◽  
The Brain ◽  
Maxillary Palps ◽  
Stimulation Of

1. The electrical resistance across the tips of the maxillary palps is not affected by stimulation of the palps, but increases to the normal level found after feeding as a result of distension of the foregut with agar or injection of corpus cardiacum homogenates into the haemolymph. 2. No increase in resistance occurs if the posterior pharyngeal nerves or the frontal connectives are cut. 3. It is inferred that distension of the foregut stimulates stretch receptors which, acting via the posterior pharyngeal nerves, the frontal connectives and the brain, cause the release of hormone from the storage lobes of the corpora cardiaca. This hormone acts on the terminal sensilla of the palps, causing them to close and so increasing the resistance across the palps. 4. Release of the diuretic hormone is controlled via the same pathway.

Testing for Density-Dependent Marine Survival in Pacific Salmonids

1978 ◽  
Vol 35 (11) ◽  
pp. 1434-1450 ◽  
Author(s):  
Randall M. Peterman
Keyword(s):  
Survival Rate ◽  
Key Words ◽  
Survival Data ◽  
Statistical Tests ◽  
Frequency Of Occurrence ◽  
Density Dependent ◽  
Key Words Density ◽  
Marine Survival ◽  
Pacific Salmonids

Marine survival data for several different salmonid stocks were reviewed to determine whether there was significant density-dependent survival occurring in the ocean. Four classes of interaction were examined: (1) within-cohorts, (2) between-cohorts, (3) between stocks on the same or nearby rivers, and (4) between stocks of distant rivers. Results of statistical tests indicate that some stocks do not produce an increase in adult returns with increased smolt abundance, and that marine survival rate of other stocks is affected by abundance of other cohorts or stocks. Only a few stocks exhibit these density-dependent relations, but given present data, it is impossible to predict the frequency of occurrence of such limiting processes in future enhanced stocks. Salmonid enhancement planning is discussed in the context of this uncertainty and experimental enhancement projects are suggested that aim to obtain information about marine survival processes as well as additional catches. Key words: density dependent, marine survival, salmonids, experimental enhancement, stock interaction, adaptive

The significance of palpation by the maxillary palps of Locusta migratoria (L): an electrophysiological and behavioural study

1975 ◽  
Vol 63 (3) ◽  
pp. 701-712
Author(s):  
W. M. Blaney ◽  
A. M. Duckett
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Sensory Input ◽  
Locusta Migratoria ◽  
Behavioural Study ◽  
The Central Nervous System ◽  
Maxillary Palps

Palpation increases the amount of sensory input reaching the central nervous system compared with that obtained from sustained contact but that increase is not essential to allow discrimination. During a meal on favoured food, phagostimulatory input from the palps is not needed to drive feeding. When less favoured food is taken, phagostimulatory input from the palps may enhance feeding. Even with favoured food, the palps are important in registering inhibitory substances.

A PRACTICAL ELECTROPHYSIOLOGICAL GUIDE FOR NON-SURGICAL AND SURGICAL TREATMENT OF CARPAL TUNNEL SYNDROME

2008 ◽  
Vol 33 (1) ◽  
pp. 32-37 ◽  
Author(s):  
C. -W. CHANG ◽  
Y. -C. WANG ◽  
K. -F. CHANG
Keyword(s):  
Surgical Treatment ◽  
Carpal Tunnel Syndrome ◽  
Carpal Tunnel ◽  
Symptom Severity ◽  
Electrophysiological Tests ◽  
Severity Scores ◽  
Functional Scores ◽  
Electrophysiological Studies ◽  
Severe Group ◽  
Tunnel Syndrome

In the present study, we illustrate the use of an electrophysiological classification as a guide to the treatment of carpal tunnel syndrome (CTS). A total of 113 CTS patients were assessed with symptom severity scores, hand functional scores and electrophysiological studies. By setting criteria of electrophysiological tests, 179 hands in 113 patients were classified into mild, moderate and severe degrees of CTS. Of these, the 41 hands with severe CTS were referred for surgery. The 58 hands with moderate CTS and 80 hands with mild CTS received conservative treatment. The improvement ratios in the severe group were greater than that in the moderate and mild groups, both at 6 months and at 1 year. Eighteen hands with moderate or mild CTS returned to normal electrophysiology with the conservative treatments. No patient recovered to normal electrophysiology in the severe group. This electrophysiological classification is objective and it may serve as a useful guide for non-surgical and surgical treatment of CTS.

Electrophysiological Responses of the Terminal Sensilla on the Maxillary Palps Of Locusta Migratoria (L.) To Some Electrolytes and Non-Electrolytes

1974 ◽  
Vol 60 (2) ◽  
pp. 275-293
Author(s):  
W. M. BLANEY
Keyword(s):  
Sodium Chloride ◽  
Locusta Migratoria ◽  
Electrophysiological Study ◽  
Constant Stimulus ◽  
Maxillary Palp ◽  
Food Plant ◽  
Plant Materials ◽  
Electrophysiological Responses ◽  
Different Types ◽  
Maxillary Palps

1. Three morphologically and functionally different types of sensilla on the maxillary palp tips of Locusta migratoria are distinguished and an electrophysiological study is made of the most commonly occurring type. 2. Responses to stimulation with 0.1 M sodium chloride show impulses of one, two or three amplitude categories in different sensilla. 3. Variability of response to a constant stimulus is appreciable, both between and within sensilla. 4. Tests with a range of compounds indicate that individual neurones are capable of responses to compounds of different chemical classes. 5. Specificity of sensilla is more marked than specificity of neurones. 6. Methods of interpretation of results are evaluated and the results are discussed in the context of discrimination of food plant materials.

scholarly journals Weakly Modulated Spike Trains: Significance, Precision, and Correction for Sample Size

2002 ◽  
Vol 87 (5) ◽  
pp. 2542-2554 ◽  
Author(s):  
Chou P. Hung ◽  
Benjamin M. Ramsden ◽  
Anna Wang Roe
Keyword(s):  
Single Unit ◽  
Statistical Tests ◽  
Strong Dependence ◽  
Spike Trains ◽  
Correction Function ◽  
Natural Scenes ◽  
Electrophysiological Studies ◽  
Spike Number ◽  
Areas 17 And 18 ◽  
Using Data

Many single-unit electrophysiological studies of visual cortex have investigated strong evoked responses to simple stimuli such as oriented gratings. Experiments involving other types of stimuli, such as natural scenes, higher-order features, and surface brightness, produce single-unit responses that are more difficult to interpret. Experiments with brightness, in particular, evoke single-unit responses that are typically weakly modulated. When the brightness is generated by a visual illusion such as the Cornsweet illusion, statistical tests are often necessary to distinguish true responses from baseline fluctuations. Here, using data collected from cat Areas 17 and 18 in response to real and illusory brightness stimuli, we provide a method for detecting and quantifying weak but significant periodic responses. By randomizing spike trains (via bootstrap methods), we provide confidence levels for response significance, permitting the evaluation of both weak and strong responses. We show that because of a strong dependence on total spike number, response significance can only be appropriately determined with randomized spike trains of similar spike number. Such randomizations can be performed for both stimulus-elicited and spontaneously occurring spike trains. By developing a method for generating randomized modulated spike trains (phase-restricted randomization) from actual recordings, we calculate upper and lower confidence limits of modulated spike trains and describe how measurement precision varies as a function of total spike count. Finally, using this randomization method, we describe how a correction function can be determined to correct for measurement bias introduced at low spike counts. These methods may also be useful in the study of small but potentially significant responses in other systems.

Changes in Chemoreceptor Sensilla on the Maxillary Palps of Locusta Migratoria in Relation to Feeding

1972 ◽  
Vol 57 (3) ◽  
pp. 745-753 ◽  
Author(s):  
E. A. BERNAYS ◽  
W. M. BLANEY ◽  
R. F. CHAPMAN
Keyword(s):  
Food Deprivation ◽  
Small Proportion ◽  
Electrical Resistance ◽  
Locusta Migratoria ◽  
Chemical Stimulation ◽  
Steady Level ◽  
The Individual ◽  
Maxillary Palps

1. The electrical resistance across the tips of the maxillary palps of Locusta migratoria is high immediately after a feed, but falls to a steady level in about 2 h after feeding. 2. Only a small proportion of the individual sensilla on the domes of the palps respond to chemical stimulation immediately after feeding, but this proportion increases with the period of food deprivation. 3. Gentle manipulation of the tips of non-responsive sensilla causes them to respond. 4. It is suggested that the terminal pores of the sensilla can open and close and that the resistance across the tips of the palps varies inversely with the number of open sensilla. 5. The possible significance of the changes is discussed.

Diagnosis of keratoconus in a young male after the hint of electrophysiological test: A Case Report and Review of the Literature

2019 ◽  
Author(s):  
weiming Yan ◽  
Yupeng Wang ◽  
Yanjing Chen ◽  
Meizhu Chen
Keyword(s):  
Visual Acuity ◽  
Young Male ◽  
Corneal Topography ◽  
Fiber Layer ◽  
Fluorescein Angiogram ◽  
Case Presentation ◽  
Full Field ◽  
Lesion Location ◽  
Electrophysiological Tests ◽  
Electrophysiological Studies

Abstract Background: Keratoconus (KCN) is a bilateral and usually asymmetrical disease in which the ectatic cornea becomes conical. Diagnosis of unimproved visual acuity (VA) as KCN might sometimes be missed out due to lack of consideration. However, combination of the electrophysiology test and other common ophthalmological examinations could help to locate the lesion for the unimproved VA and realize the possibility of the existence of KCN, which could be diagnosed via corneal topography. The purpose of this report is to describe the diagnosis process of a case of KCN after the hint of lesion location by electrophysiological tests. Case presentation: A 23-year-old young male presented to our ophthalmology clinic complaining of decreased visual acuity in the left eye for 5 months. Clinical evaluation showed best corrected visual acuity of 1.0 OD, and 0.06 OS. The dilated fundus examination revealed no specific abnormality. Spectral-domain optical coherence tomography (SD-OCT) of macular revealed no obvious change on macular and the thickness of peripapillary nerve fiber layer on both eyes. No leakage of fluorecein was found under Fluorescein angiogram (FFA) of both eyes. Indocyanine green angiography (ICGA) did not showed abnormality. The full-field electroretinogram (ffERG) revealed no obvious changes of amplitudes in all responses. Pattern visual evoked potentials (PVEP) detected a reduced amplitude and delayed phase in P100-wave in both eyes. The amplitude and latency of P2-wave in Flash VEP (FVEP) were comparable in both eyes and were within normative ranges. Corneal topography was finally performed and KCN was diagnosed with the presence of asymmetrical bowtie pattern in both eyes, which was worse in the OS. Conclusions: The hint of lesion location by electrophysiological studies (ffERG, PVEP and FVEP) could be of favor to diagnose the conditions with unimproved VA, such as KCN. Consideration of KCN should be suspected in patients with unimproved VA and significant irregular stigmatism, while no obvious lesion exists in other parts of the eye.

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