Sensory motor behavior

Animal behavior has been dehned by Odnm (1971) as the overt action an organism takes to adjnst to its environment so as to ensure its survival. A simpler definition is the dynamic interaction of an animal with its enviromnent (D Mello 1992). Another, more elaborate, one is, the outward expression of the net interaction between the sensory, motor arousal, and integrative components of the central and peripheral nervons systems (Norton 1977). The last dehnition spells out the important point that behavior represents the integrated function of the nervous system. Accordingly, disruption of the nervous system by neurotoxic chemicals may be expected to cause changes in behavior (see Klaasen 1996, pp. 466-467). 

Behavioral and cognitive effects As might be expected, ibogaine has powerful sensory and motor effects. Rats administered ibogaine (20-60 mg/kg) show slower response times on sensory and sensory-motor tests (Kesner et al. 1995). Motor reflexes are impaired at 40-60 mg/kg, and... 

Epilepsy is a chronic neurologic disorder characterized by recurrent seizures.33 Seizures are episodes of sudden, transient disturbances in cerebral excitation that occur when a sufficient number of cerebral neurons begin to fire rapidly and in synchronized bursts.42 Depending on the type of seizure, neuronal activity may remain localized in a specific area of the brain, or it may spread to other areas of the brain. In some seizures, neurons in the motor cortex are activated, leading to skeletal muscle contraction via descending neuronal pathways. These involuntary, paroxysmal skeletal muscle contractions seen during certain seizures are referred to as convulsions. However, convulsions are not associated with all types of epilepsy, and other types of seizures are characterized by a wide variety of sensory or behavioral symptoms. 

The cerebral cortex of the brain is an approximately continuous, homogenous neural medium, which is molded (or rutted ) into preferred tracks of neural transmission by imprinting and by repeated activity (i.e., behavioral learning). Within this system, there exists a relatively discrete series of dimensions ("levels ) within which recurrent circular operations stabilize existing patterns (1) the sensory-motor loop, representing interaction with the physical/behavioral space outside, and (2) an internal behavior loop, which operates even in isolation from the... 

So far the discussion of firing patterns of the cells have been restricted to those seen in the most common preparations but the function of dopamine is surely best studied in conscious animals able to move and respond to external cues. In the past decade such recordings have begun to paint a very intriguing picture of the role of dopamine cells in animal behavior. Early studies of this type had been disappointing from the point of view of the involvement of dopamine cells in motor behavior. In cats (Trulson and Jacobs, 1979 Trulson, 1985) and monkeys (Schultz, 1986) it seemed that the dopamine cells were not responsive to the present behavior of the animal. Few, if any, the cells responded either to the movements in a motor task or to the sensory cues guiding the behavior. 

In this section we review both the acute and chronic effects of alcohol consumption. We first go over alcohol s many acute physiological, sensory-motor (sensorimotor), and psychological effects. We also di.scuss several topics of special societal concern related to alcohol s acute effects, including aggression, sexual behavior, and driving. 

Effects of the test substance on the central nervous system should be assessed appropriately. Motor activity, behavioral changes, coordination, sensory/ motor reflex responses, analgesia test (hot plate), proconvulsant activity, barbiturate-induced sleeping time, and body temperature should be evaluated. For example, a functional observation battery, modified Irwin s, or other appropriate tests can be used. 

Influence/effects not apparent or obvious Behavior nearly normal by ordinary observation Impairment detectable by special tests Mild euphoria, sociability, talkativeness Increased self-confidence decreased inhibitions Diminution of attention, judgment, and control Some sensory-motor impairment Slowed information processing Loss of efficiency in finer performance tests Emotion instability loss of critical judgment Impairment of perception, memory, and comprehension... 

Effects of the compound on specific organ systems, i.e., cardiovascular, respiratory, and nervous, are evaluated. These are referred to as safety pharmacology studies and are intended to investigate the potential undesirable pharmacodynamic effects of a substance on physiological functions in relation to exposure. Parameters that are evaluated include blood pressure, heart rate, electrocardiogram, motor activity, behavioral changes, coordination, sensory/motor reflex responses, respiratory rate and depth (6,7). 

Toxicologic Data" and the "Workshop on the Effects of Pesticides on Human Health" which was organized by the Task Force on Environmental Cancer, Heart and Lung Disease) have recommended methods and test batteries that would detect sensory, motor, autonomic, cognitive and behavioral dysfunction. 

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