British Poultry Science
ISSN: 0007-1668 (Print) 1466-1799 (Online) Journal homepage: http://www.tandfonline.com/loi/cbps20
Using arousal changes in the EEG to indicate gustatory sensitivity following brain lesion in Gallus domesticus M. J. Gentle To cite this article: M. J. Gentle (1976) Using arousal changes in the EEG to indicate gustatory sensitivity following brain lesion in Gallus domesticus , British Poultry Science, 17:2, 151-156, DOI: 10.1080/00071667608416260 To link to this article: http://dx.doi.org/10.1080/00071667608416260
Published online: 08 Nov 2007.
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Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=cbps20 Download by: [University of Florida]
Date: 07 November 2015, At: 17:54
Br. Poult. Set., 17: 151-156.
1976
Longman: printed in Great Britain
USING AROUSAL CHANGES IN THE EEG TO INDICATE GUSTATORY SENSITIVITY FOLLOWING BRAIN LESION IN GALLUS DOMESTICUS M. J. GENTLE Agricultural Research Council's Poultry Research Centre, King's Buildings, West Mains Road, Edinburgh EH9 3JS, Scotland Downloaded by [University of Florida] at 17:54 07 November 2015
Received for publication 24th February 1975
1. The EEG of Gallus domesticus was recorded before and after brain lesions following stimulation with light, sound and taste. 2. It was found that under the conditions of the experiment the lesions did not have any general effect on the arousal mechanism of the animal. 3. Bilateral lesions in the stratum cellulare externum of one animal had a specific effect on the arousal response to a quinine hydrochloride solution and it was concluded that it is possible to indicate deficits following brain lesion in the gustatory system using the EEG. INTRODUCTION
One of the problems in gustatory physiology in chickens is the determination of perceptual thresholds of taste sensitivity especially after brain lesion. Behavioural measures give preference/aversion curves but it can always be argued that the lesion may have affected parts of the brain which are not related to the sense directly, but are part of the rejection/preference system of the animal. Previous work (Gentle, 1972, 1975a) has shown that it is possible to measure perceptual thresholds to taste sensitivity using arousal changes in the EEG. The length of the EEG arousal pattern was measured following oral presentation of distilled water or a chemical solution. It was found that repeated presentation of distilled water led to habituation and that the orienting reflex could be elicited by the presentation of a stimulating chemical in place of the water. This technique has been used to show that many solutions of chemicals which do not produce any behavioural responses are in fact perceived by the animal. The present experiment is an extension of this work and demonstrates that by using arousal changes in the EEG it may be possible to indicate specific changes in taste sensitivity following brain lesion. MATERIALS AND METHODS
Animals
Seven Brown Leghorn hens each weighing 1-5 kg were used. They were bred at the Poultry Research Centre and housed in individual cages, with food and water 151
152
M. J. GENTLE
freely available. The temperature of the poultry house was maintained at 22 ±1-7 °G and illuminated from 0700 to 2100 h.
Downloaded by [University of Florida] at 17:54 07 November 2015
Surgical procedure
Anaesthesia for surgery was induced using sodium pentobarbitone (Nembutal, Abbott Laboratories Ltd) and maintained with methoxyflurane (Penthrane, Abbott Laboratories Ltd). The details of the electrodes used to record the EEG and their placement are given elsewhere (Gentle, 1972; Gentle and Richardson, 1972). The electrodes used to produce the lesions were made from 300 jum diameter silver wire, straightened and implanted stereotactically at the same time as the EEG electrodes, using the van Tienhoven and Juhasz (1962) atlas. All the electrodes were attached to a DIN socket (R.S. Components Ltd) which was anchored to the skull by two nylon screws and dental acrylic. A stainless-steel cannula was implanted through the upper beak to allow the water to be injected directly into the mouth. Apparatus
The water was injected using a dispenser (Fison Ltd) and the EEG was recorded using a Type 111A F.E.T. preamplifier (C. F. Palmer, London), main amplifiers (Fylde Electronic Laboratories Ltd) and was displayed on an ultraviolet oscilloscope (Bell and Howell Ltd). The preamplifier was set with a 200 ms time constant and a high-frequency filter of 1 kHz. The birds were also stimulated with light using a 12 V, 0-1 A light bulb placed 10 cm from the animal's head. Auditory stimulation was produced by a 4 V door buzzer (Gent) attached to the side of the box. Experimental method
The birds were removed from their cages and placed in a " V " shaped partial restraint box in darkness. The animal had previously been trained to accept this restraint. They were allowed 3 min before being presented with the first stimulus and were then given a series of six successive injections of 0-5 ml of deionised water, one every 4 min, with each injection lasting 1-5 s. After the sixth water stimulus they were given two tests with 0-5 ml of 0-005M quinine hydrochloride. The twinbore vinyl tubing attached to the beak cannula enabled this to be done without disturbing the birds. The water and quinine hydrochloride (QHG1) were injected into the mouth at 22 °G. Quinine hydrochloride at 0-005M produced a significant reduction (P
ISSN: 0007-1668 (Print) 1466-1799 (Online) Journal homepage: http://www.tandfonline.com/loi/cbps20
Using arousal changes in the EEG to indicate gustatory sensitivity following brain lesion in Gallus domesticus M. J. Gentle To cite this article: M. J. Gentle (1976) Using arousal changes in the EEG to indicate gustatory sensitivity following brain lesion in Gallus domesticus , British Poultry Science, 17:2, 151-156, DOI: 10.1080/00071667608416260 To link to this article: http://dx.doi.org/10.1080/00071667608416260
Published online: 08 Nov 2007.
Submit your article to this journal
Article views: 7
View related articles
Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=cbps20 Download by: [University of Florida]
Date: 07 November 2015, At: 17:54
Br. Poult. Set., 17: 151-156.
1976
Longman: printed in Great Britain
USING AROUSAL CHANGES IN THE EEG TO INDICATE GUSTATORY SENSITIVITY FOLLOWING BRAIN LESION IN GALLUS DOMESTICUS M. J. GENTLE Agricultural Research Council's Poultry Research Centre, King's Buildings, West Mains Road, Edinburgh EH9 3JS, Scotland Downloaded by [University of Florida] at 17:54 07 November 2015
Received for publication 24th February 1975
1. The EEG of Gallus domesticus was recorded before and after brain lesions following stimulation with light, sound and taste. 2. It was found that under the conditions of the experiment the lesions did not have any general effect on the arousal mechanism of the animal. 3. Bilateral lesions in the stratum cellulare externum of one animal had a specific effect on the arousal response to a quinine hydrochloride solution and it was concluded that it is possible to indicate deficits following brain lesion in the gustatory system using the EEG. INTRODUCTION
One of the problems in gustatory physiology in chickens is the determination of perceptual thresholds of taste sensitivity especially after brain lesion. Behavioural measures give preference/aversion curves but it can always be argued that the lesion may have affected parts of the brain which are not related to the sense directly, but are part of the rejection/preference system of the animal. Previous work (Gentle, 1972, 1975a) has shown that it is possible to measure perceptual thresholds to taste sensitivity using arousal changes in the EEG. The length of the EEG arousal pattern was measured following oral presentation of distilled water or a chemical solution. It was found that repeated presentation of distilled water led to habituation and that the orienting reflex could be elicited by the presentation of a stimulating chemical in place of the water. This technique has been used to show that many solutions of chemicals which do not produce any behavioural responses are in fact perceived by the animal. The present experiment is an extension of this work and demonstrates that by using arousal changes in the EEG it may be possible to indicate specific changes in taste sensitivity following brain lesion. MATERIALS AND METHODS
Animals
Seven Brown Leghorn hens each weighing 1-5 kg were used. They were bred at the Poultry Research Centre and housed in individual cages, with food and water 151
152
M. J. GENTLE
freely available. The temperature of the poultry house was maintained at 22 ±1-7 °G and illuminated from 0700 to 2100 h.
Downloaded by [University of Florida] at 17:54 07 November 2015
Surgical procedure
Anaesthesia for surgery was induced using sodium pentobarbitone (Nembutal, Abbott Laboratories Ltd) and maintained with methoxyflurane (Penthrane, Abbott Laboratories Ltd). The details of the electrodes used to record the EEG and their placement are given elsewhere (Gentle, 1972; Gentle and Richardson, 1972). The electrodes used to produce the lesions were made from 300 jum diameter silver wire, straightened and implanted stereotactically at the same time as the EEG electrodes, using the van Tienhoven and Juhasz (1962) atlas. All the electrodes were attached to a DIN socket (R.S. Components Ltd) which was anchored to the skull by two nylon screws and dental acrylic. A stainless-steel cannula was implanted through the upper beak to allow the water to be injected directly into the mouth. Apparatus
The water was injected using a dispenser (Fison Ltd) and the EEG was recorded using a Type 111A F.E.T. preamplifier (C. F. Palmer, London), main amplifiers (Fylde Electronic Laboratories Ltd) and was displayed on an ultraviolet oscilloscope (Bell and Howell Ltd). The preamplifier was set with a 200 ms time constant and a high-frequency filter of 1 kHz. The birds were also stimulated with light using a 12 V, 0-1 A light bulb placed 10 cm from the animal's head. Auditory stimulation was produced by a 4 V door buzzer (Gent) attached to the side of the box. Experimental method
The birds were removed from their cages and placed in a " V " shaped partial restraint box in darkness. The animal had previously been trained to accept this restraint. They were allowed 3 min before being presented with the first stimulus and were then given a series of six successive injections of 0-5 ml of deionised water, one every 4 min, with each injection lasting 1-5 s. After the sixth water stimulus they were given two tests with 0-5 ml of 0-005M quinine hydrochloride. The twinbore vinyl tubing attached to the beak cannula enabled this to be done without disturbing the birds. The water and quinine hydrochloride (QHG1) were injected into the mouth at 22 °G. Quinine hydrochloride at 0-005M produced a significant reduction (P
