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J C Fentress

Publications and source records attributed to J C Fentress.

At least 19 recordsLinked to original sources
PubMed1992

History of developmental neuroethology: early contributions from ethology.

Ethology has its roots in the natural history of animal behavior. Questions of causation and function have historically been complementary, and each has rested upon a prior appreciation of the behavior of animals in nature. It is thus difficult to place a single time or place where ethology was born. Early evolutionary interests hinted at developmental constraints that continue to guide much research. It has only been relatively recently, however, that the explicit analysis of neural mechanisms in behavior has received the attention it deserves in developmental analyses. A mature developmental neuroethology will require a synthesis of the broad insights of ethology with refined neurobiological technique. Fundamental, however, is the primary focus upon behavior as it normally occurs.

Animals↗
PubMed1992

Emergence of pattern in the development of mammalian movement sequences.

The manner in which behavior is patterned in space and over time represents a fundamental problem in both ethology and neuroscience. Prior to the analysis of mechanism it is important to be sensitive to issues involved in the provision of descriptive taxonomies. Often alternative modes of description lead to different perspectives and research strategies. In both the development of behavioral patterns and their expression a major question is how underlying organizational systems become self-organizing through the process of mutual interactions. It is clear that simple static dichotomies in both behavioral and developmental science must be replaced by more sophisticated models that emphasize the dynamics of pattern formation and control. Some of these perspectives are illustrated from our ongoing research on rodent movement patterns.

Animals↗
PubMed1991

Food caching in captive coyotes: stereotypy of action sequence and spatial distribution of cache sites.

This paper describes some aspects of the food caching behaviour of four captive coyotes. Detailed observations of the actions used by coyotes to cache food revealed them to be strikingly similar to those previously described for timber wolves. The similarities included the identity of the movements used, their temporal sequencing, and their susceptibility to interruption. This suggests that there exists a stereotypy across canids in the action sequences used in caching. Second, an examination of the distribution of cache sites revealed that each coyote scattered cache sites widely within a wooded region of their enclosure and preferentially in terrains close to exposed tree roots.

Animals↗
PubMed1991

Evaluation of immunoassay methods for the screening of cocaine metabolites in urine.

Immunoassay kits for urine cocaine (and metabolite) screening, obtained from two commercial sources, were examined for correlation of their results, expressed in terms of equivalent benzoylecgonine concentration, with the gas chromatography/mass spectrometry (GC/MS) concentration of benzoylecgonine. The correlation coefficients obtained, based on 62 (out of a total sample population of 3295) highly relevant samples, were 0.467 and 0.766 for Abuscreen (ARIA) and TDx (TDX), respectively. The preliminary screen cutoff values, which correspond to 150 ng/mL benzoylecgonine (as determined by GC/MS), were calculated based on the resulting regression equations and found to be 380 and 190 ng/mL for ARIA and TDX, respectively. With these cutoff values, ARIA generates 5 false negatives and 16 unconfirmed presumptive positives, while TDX results in 3 false negatives and 6 unconfirmed presumptive positives.

Binding, Competitive↗
PubMed1990

Food-caching in timber wolves, and the question of rules of action syntax.

This report presents data on the sequence of motor operations used by captive timber wolves to cache food. Videotapes were obtained of 151 caching episodes by 8 wolves. The vast majority of these episodes contained 3 distinct phases, each composed of movements unique to that phase. The excavation of the cache site was always done with the forefeet, and burying of the food was always done with the snout. Both the identity of the movements, and the serial order of phases were independent of the sex of the animal, the season in which the observations were made, and the nature of the substrate. A comparison of the temporal sequencing of these actions with the temporal stereotypy seen in rodent motor patterns (e.g. grooming) revealed a striking phenomenological similarity. The factors shaping the temporal sequencing in the two behaviors are, however, probably very different. This is because much, though not all, of the temporal stereotypy in the sequence of movements used by the wolf in caching is constrained by the logistics of the cache operation, while this is not the case for the phases of facial grooming in rodents. The implications of our data for the kinds of behavioral evidence required for ascription of such stereotypy to a central pattern generator are discussed.

Animals↗
PubMed1988

A triggered hyperkinesia induced in rats by lesions of the corpus striatum.

The role of the corpus striatum (caudate, putamen, and globus pallidus) in movement control has been suggested to involve the modulation of sensory traffic to downstream motor mechanisms. We report that kainic acid lesions of the posterior corpus striatum, which preferentially spare fibers of passage while destroying striatopallidal neurons, produce a stimulus-sensitive movement pattern in rats that has a highly specific sensory trigger. The triggered choreic movement pattern is not a motor pathology per se, nor a response to diffuse states of arousal or stress, but rather is activated specifically in response to oral sensory stimulation. This sensory-specific hyperkinesia may be relevant to certain human sensorimotor pathologies.

Animals↗
PubMed1987

Natural syntax rules control action sequence of rats.

Knowledge of the principles by which behavioral sequences are generated is essential to progress in our understanding of neural mechanisms. We describe here a set of natural principles or syntax rules that organize the components of grooming and feeding. The behavioral stream of facial grooming or of taste-elicited ingestive/aversive consummatory actions of rats can be viewed as a long series of individual movements linked together to form functional sequences. In order to ascertain the syntax rules that determine how these actions are linked together, many thousands of spontaneous grooming and elicited ingestive/aversive actions were videotaped and scored with a microcomputer. Techniques of information analysis of sequential stereotypy, tabulation of the sequential transitions between single actions and between action groups, and visual inspection for linear action chains, were employed to expose underlying rules of behavioral sequencing. These analyses revealed two global patterns: action perserveration and transitional reciprocation between sequential pairs and triplets, which together account for approximately 75% of all sequential transitions during grooming and ingestion/aversion. The pattern of transitional reciprocation could be divided further into patterns of alternation between individual actions on the one hand, and between perseverating bouts of actions on the other. Global syntax rules applied equally to actions emitted during grooming or during taste-elicited ingestion/aversion. In addition, a specific rule of linear chaining was found to apply only to facial grooming. These natural rules of action syntax provide insight into the sequential structure of behavior, and lend themselves well to analyses of neural mechanisms.

Animals↗
PubMed1987

Deafferentation does not disrupt natural rules of action syntax.

Natural rules of action syntax control the sequential order of grooming and ingestive/aversive actions emitted by rats. Grooming and ingestive actions share a common feature in that all are performed with or directed towards the mouth, tongue, and face. This study examined the role of orofacial somatosensory cues and feedback in the generation of natural action syntax. Bilateral deafferentation of the mandibular and maxillary branches of the trigeminal nerve was used to eliminate tactile sensation from the rostral face and mouth while preserving motor function. Neither the overall degree of sequential stereotypy (H) of grooming or ingestive sequences, nor the generation of particular natural sequencing rules were affected by trigeminal deafferentation. These natural rules appear to be specified by the brain without need of somatosensory feedback.

Afferent Pathways↗
PubMed1986

Contextual control of trigeminal sensorimotor function.

Simple actions, such as rhythmic tongue protrusions, forelimb facial strokes, and forelimb flails, are emitted by rats both during taste-elicited ingestion/aversion and during postprandial grooming. This study combined peripheral trigeminal deafferentation with a computer-assisted video analysis of action form to examine the use of cutaneous feedback from the face in action production. Changes in action form after deafferentation were found to be context-dependent: Deformations characterized rhythmic tongue protrusions when emitted in ingestive but not in grooming contexts. The opposite was true for alterations in forelimb action. Further, postprandial grooming as a whole was found to comprise distinct sequentially defined phases. Actions occurring in one highly stereotyped sequence phase were protected from deafferentation effects, although the same actions occurring outside of this phase were not. The results suggest that behavioral context (e.g., grooming versus ingestive set, sequence phase) can shift the integration of sensory guided and endogenous mechanisms that pattern simple actions.

Animals↗
PubMed1985

Trigeminal-taste interaction in palatability processing.

Peripheral transection of the sensory branches of the trigeminal nerve in rats unbalanced palatability, selectively reducing the ingestive actions elicited by preferred tastes but leaving unchanged the aversive actions elicited by unpreferred tastes. The reduction in the number of positive ingestive actions occurred even though the capacity to emit these actions remained unimpaired. These findings show that there is an interaction between somatosensation and gustation in the processing of palatability.

Animals↗
PubMed1985

Early ontogeny of face grooming in mice.

A U-shaped function of behavioral growth characterizes the early ontogeny of face grooming in mice. In the first few postnatal days (0-100 hr), mice groom their face by using temporally isolated strokes, or bouts of strokes, which vary in amplitude and symmetry. Later on (100-200 hr), bouts disappear, asymmetry is eliminated, and the amplitude of strokes is gradually restricted; the infants engage in stereotyped, double-handed, temporally isolated strokes. Finally (200-300 hr), bouts reappear, including both short and long, symmetrical and asymmetrical, strokes. These changes, are accompanied by unidirectional changes such as an increasing participation of the trunk, the neck, and the head in grooming, which lead to the flexible organization of face grooming seen in adults. Instead of describing development in terms of emerging unitary "acts," we have recorded from high-speed films three simultaneous aspects of movement: the movements of the separate limb and body segments, the resultant paths which are traced by the forepaws, and the paths of contact which are traced on the face. This method of description discloses (a) reversible changes, and (b) a change in the relative stability of each of these aspects of face grooming, in the course of early ontogeny.

Animals↗
PubMed1973

Development of grooming in mice with amputated forelimbs.

Face grooming sequences that involve coordination of the shoulders, tongue, and eyes develop remarkably normally in inbred mice with one or both forelimbs amputated from birth. This indicates endogenous control with a strong genetic component. Evidence for the maturational expression of "sensory expectations" was also obtained.

Amputation, Surgical↗