When correlating brain areas with behavioral and environmental characteristics, a variety of techniques are employed. In fishes (elasmobranchs and teleosts), 2 methods, histology and the idealized ellipsoid and/or half-ellipsoid technique, are primarily used to calculate the volume of a brain area and therefore its relationship to social or ecological complexity. In this study on a perciform teleost, we have quantitatively compared brain volumes obtained using the conventional techniques of histology and approximating brain volume to an idealized ellipsoid (or half ellipsoid) and magnetic resonance imaging, an established clinical tool typically used for assessing brain volume in other vertebrates. Our results indicate that, when compared to brain volumes measured using magnetic resonance imaging of brain regions in situ, variations in brain shape and histological artifacts can lead to significant differences in brain volume, especially in the telencephalon and optic tecta. Consequently, in comparative studies of brain volumes, we advise caution when using the histological and/or ellipsoid methods to make correlations between brain area size and environmental, behavioral and social characteristics and, when possible, we propose the use of magnetic resonance imaging.

Bahr GF, Bloom G, Friberg U (1957): Volume changes of tissue in physiological fluids during fixation in osmium tetroxide or formaldehyde and during subsequent treatment. Exp Cell Res 12:342–355.
Barton RA (1996): Neocortex size and behavioral ecology in primates. Proc Biol Sci 263:173–177.
Broglio C, Rodriguez F, Gomez A, Arias JL, Salas C (2010): Selective involvement of the goldfish lateral pallium in spatial memory. Behav Brain Res 210:191–201.
Burns JG, Rodd FH (2008): Hastiness, brain size and predation regime affect the performance of wild guppies in a spatial memory task. Anim Behav 76:911–922.
Burns JG, Saravanan A, Rodd FH (2009): Rearing environment affects the brain size of guppies: lab-reared guppies have smaller brains than wild-caught guppies. Ethology 115:122–133.
Butler AB, Hodos W (2005): Comparative Vertebrate Neuroanatomy, ed 2. Hoboken, John Wiley and Sons.
Caprio J, Brand JG, Teeter JH, Valentincic T, Kalinoski DL, Kohbara J, Kumazawa T, Wegert S (1993): The taste system of the channel catfish: from biophysics to behavior. Trends Neurosci 16:192–197.
Corfield JR, Wild JM, Cowan BR, Parsons S, Kubke MF (2008): MRI of postmortem specimens of endangered species for comparative brain anatomy. Nat Protocols 3:597–605.
Davis RE, Northcutt RG (1983): Fish Neurobiology. Ann Arbor, University of Michigan Press.
Doherty CP, Fitzsimons M, Holohan T, Mohamed HB, Farrell M, Meredith GE, Staunton H (2000): Accuracy and validity of stereology as a quantitative method for assessment of human temporal lobe volumes acquired by magnetic resonance imaging. Magn Reson Imaging 18:1017–1025.
Garcia-Finana M, Cruz-Orive LM, Mackay CE, Pakkenberg B, Roberts N (2003): Comparison of MR imaging against physical sectioning to estimate the volume of human cerebral compartments. Neuroimage 18:505–516.
Gonda A, Herczeg G, Merila J (2009): Habitat-dependent and -independent plastic responses to social environment in the nine-spined stickleback (Pungitius pungitius) brain. Proc Royal Soc Lond B 276:161–167.
Gonzalez-Voyer A, Winberg S, Kolm N (2009): Brain structure evolution in a basal vertebrate clade: evidence from phylogenetic comparative analysis of cichlid fishes. BMC Evol Biol 9:238.
Grace AA, Llinas R (1985): Morphological artifacts induced in intracellularly stained neurons by dehydration: circumvention using rapid dimethyl sulfoxide clearing. Neuroscience 16:461–475.
Haug H (1986): History of neuromorphometry. J Neurosci Methods 12:1–17.
Healy S, Guilford T (1990): Olfactory-bulb size and nocturnality in birds. Evolution 44:339–346.
Healy SD, Rowe C (2006): A critique of comparative studies of brain size. Proc Royal Soc Lond B 274:453–464.
Huber R, Van Staaden MJ, Kaufman LS, Liem KF (1997): Microhabitat use, tropic patterns, and the evolution of brain structure in African cichlids. Brain Behav Evol 50:167–182.
Iwaniuk AN, Nelson JE (2002): Can endocranial volume be used as an estimate of brain size in birds. Can J Zool 80:16–23.
Jelsing J, Rostrup E, Markenroth K, Paulson OB, Gundersen HJG, Hemmingsen R, Pakkenberg B (2005): Assessment of in vivo MR imaging compared to physical sections in vitro: a quantitative study of brain volumes using stereology. NeuroImage 26:57–65.
Kanwal JS, Caprio J (1987): Central projections of the glossopharyngeal and vagal nerves in the channel catfish, Ictalurus punctatus: clues to differential processing of visceral inputs. J Comp Neurol 264:216–230.
Kihslinger RL, Lema SC, Nevitt GA (2006): Environmental rearing conditions produce forebrain differences in wild chinook salmon Oncorhynchus tshawytscha. Comp Biochem Physiol A Mol Integr Physiol 145:145–151.
Kihslinger RL, Nevitt GA (2006): Early rearing environment impacts cerebellar growth in juvenile salmon. J Exp Biol 209:504–509.
Kim TH, Zollinger L, Shi XF, Rose J, Jeong EK (2009): Diffusion tensor imaging of ex vivo cervical spinal cord specimens: the immediate and long-term effects of fixation on diffusivity. Anat Rec 292:234–241.
Kolm N, Gonzalez-Voyer A, Brelin D, Winberg S (2009): Evidence for small scale variation in the vertebrate brain: Mating strategy and sex affect brain size and structure in wild brown trout (Salmo trutta). J Evol Biol 22:2524–2531.
Kotrschal K, Junger H (1988): Patterns of brain morphology in mid-European cyprinidae (Pisces, Teleostei): a quantitative histological study. J Hirnforsch 29:341–352.
Kotrschal K, Palzenberger M (1992): Neuroecology of cyprinids: comparative, quantitative histology reveals diverse brain patterns. Environ Biol Fishes 33:135–152.
Kotrschal K, Van Staaden MJ, Huber R (1998): Fish brains: evolution and environmental relationships. Rev Fish Biol Fisheries 8:373–408.
LaDage LD, C. RIT, Pravosudov VV (2009): Biases in measuring the brain: the trouble with the telencephalon. Brain Behav Evol 73:253–258.
Lisney TJ, Collin SP (2006): Brain morphology in large pelagic fishes: a comparison between sharks and teleosts. J Fish Biol 68:532–554.
Lisney TJ, Bennett MB, Collin SP (2007): Volumetric analysis of sensory brain areas indicates ontogenetic shifts in the relative importance of sensory systems in elasmobranchs. Raffles Bull Zool 14:7–15.
Lisney TJ, Yopak KE, Montgomery JC, Collin SP (2008): Variation in brain organization and cerebellar foliation in chondrichthyans: Batoids. Brain Behav Evol 72:262–282.
Maler L, Karten HJ, Bennett MVL (1973): The central connections of the anterior lateral line nerve of Gnathonemus petersii. J Comp Neurol 151:67–84.
Mayhew TM, Olsen DR (1991): Magnetic resonance imaging (MRI) and model-free estimates of brain volume determine using the cavalieri principle. J Anat 178:133–144.
Nieuwenhuys R, Meek J (1998): Holosteans and teleosts; in Nieuwenhuys R, Ten Donkelaar HJ, Nicholoson C (eds): The Central Nervous System of Vertebrates. Berlin, Springer, vol 2, pp 759–938.
Northcutt RG (2002): Understanding vertebrate brain evolution. Integr Comp Biol 42:743–756.
Park PJ, Bell MA (2010): Variation of telencephalon morphology of the threespine stickleback (Gasterosteus aculeatus) in relation to inferred ecology. J Evol Biol 23:1261–1277.
Pollen AA, Dobberfuhl AP, Scace J, Igulu MM, Renn SCP, Shumway CA, Hofmann HA (2007): Environmental complexity and social organization sculpt the brain in lake tanganyikan cichlid fish. Brain Behav Evol 70:21–39.
Purea A, Webb AG (2006): Reversible and irreversible effects of chemical fixation on the NMR properties of single cells. Magn Reson Med 56:927–931.
Reader SM, Laland KN (2002): Social intelligence, innovation, and enhanced brain size in primates. Proc Natl Acad Sci 99:4436–4441.
Rosen GD, Harry JD (1990): Brain volume estimation from serial section measurements: a comparison of methodologies. J Neurosci Methods 35:115–124.
Shultz S, Dunbar RIM (2006): Both social and ecological factors predict ungulate brain size. Proc Royal Soc Lond B 273:207–215.
Stowell RE (1941): Effect on tissue volume of various methods of fixation, dehydration, and embedding. Biotech Histochem 16:67–83.
Striedter GF (2005): Principles of Brain Evolution. Sunderland, Sinauer Associates.
Ullmann JFP, Cowin G, Kurniawan ND, Collin SP (2010a): A three-dimensional digital atlas of the zebrafish brain. Neuroimage 51:76–82.
Ullmann JFP, Cowin G, Collin SP (2010b): Magnetic resonance microscopy of the barramundi (Lates calcarifer) brain. J Morphol, in press.
Ullmann JFP, Cowin G, Kurniawan ND, Collin SP (2010c): Magnetic resonance histology of the adult zebrafish brain: optimization of fixation and gadolinium contrast enhancement. NMR Biomed 23:341–346.
Uylings HBM, van Eden CG, Hofman MA (1986): Morphometry of size/volume variables and comparison of their bivariate relations in the nervous system under different conditions. J Neurosci Methods 18:19–37.
van Staaden MJ, Huber R, Kaufman LS, Liem KF (1995): Brain evolution in cichlids of the african great lakes: brain and body size, general patterns, and evolutionary trends. Zoology 98:165–178.
Wagner HJ (2001a): Sensory brain areas in mesopelagic fishes. Brain Behav Evol 57:117–133.
Wagner HJ (2001b): Brain areas in abyssal demersal fishes. Brain Behav Evol 27:301–316.
Wagner HJ (2002): Sensory brain areas in three families of deep-sea fish (slickheads, eels, and grenadiers): comparison of mesopleagic and demersal species. Marine Biol 141:807–817.
Wagner HJ (2003): Volumetric analysis of brain areas indicates a shift in sensory orientation during development in the deep-sea grenadier Coryphaenoides armatus. Marine Biol 142:791–797.
Weil A (1928): The measurement of cerebral and cerebellar surfaces. V. The determination of the shrinkage of the surface of different vertebrate brains. Arch Neurol Psychiatry 20:834–835.
Westbrook C, Roth CK, Talbot J (2005): MRI in Practice, ed 3. Oxford, Blackwell Science.
Wullimann MF, Rupp B, Reichert H (1996): Neuroanatomy of the Zebrafish Brain: A Topological Atlas. Basel, Birkhäuser.
Wullimann MF, Mueller T (2004): Teleostean and mammalian forebrain contrasted: evidence from genes to behavior. J Comp Neurol 475:143–162.
Yopak KE, Frank LR (2009): Brain size and brain organization of the whale shark, Rhincodon typus, using magnetic resonance imaging. Brain Behav Evol 74:121–142.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.