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EEO Upward Mobility Program participants were compared with three different control groups along I-E locus of control dimensions. With this instrument and these Ss, no significant differences were found when participation in the program was used as an indicator of goal-directed behavior.
Cortical areas were explored with regard to saccade control: the lateral intraparietal (LIP) area is involved in the spatial aspects of sensorimotor processing; the supplementary motor area in goal-directed gaze control; and from lesion studies; the posterior parietal cortex in triggering visually guided saccades. Different studies have suggested that the spatial-to-temporal transformation takes place in the superior colliculus (SC) and the cerebellum. When the vestibulo-ocular reflex (VOR) produces inadequate eye movements, other supplementary mechanisms (e.g. non-visual, saccade) may play a role in correcting gaze. A classification of central vestibular disorders of the brainstem and VOR has been proposed, as manifested in any one of the three major planes of action (yaw, pitch and role).
Avoidance behaviour is fundamental for survival but can become maladaptive in clinical conditions. A large body of literature has accumulated on the dynamics of human avoidance learning. However, current theories and overviews do not provide an exhaustive account of this evidence. In this systematic review, we identify N = 116 studies on human avoidance learning. We analyse these studies with the goal of distilling robust empirical phenomena as a basis for theory-building, and examine their diagnostic value in differentiating between competing theories. We find that the evidence is difficult to reconcile with foundational two-factor and classical safety-signal accounts, and most strongly supports expectancy- and inference-based views, in which avoidance responses are selected with respect to represented consequences. At the same time, no current framework provides a complete account of the evidence: several findings point to an additional role for operant valuation, Pavlovian influences, and contextual or latent-state control over the expression of avoidance. Methodologically, we observe that the problem setting in the most common experimental paradigms is radically simpler than real-world avoidance and therefore unlikely to expose the limits of inferential or reflective mechanisms. Consequently, we argue that paradigms with greater computational demands and more realistic action affordances are required to identify the mechanisms underlying avoidance learning. Collectively, these insights provide a foundation for theoretical refinement, computational modelling, and methodological innovation, with implications for advancing interventions targeting maladaptive avoidance.
Projections from cortical and subcortical limbic structures to the basal ganglia are predominantly directed to the ventral striatum. The present study investigated how the expectation of external events with behavioral significance is reflected in the activity of ventral striatal neurons. A total of 420 neurons were studied in macaque monkeys performing in a delayed go-no-go task. Lights of different colors instructed the animal to do an arm-reaching movement or refrain from moving, respectively, when a trigger light was illuminated a few seconds later. Task performance was reinforced by liquid reward in both situations. A total of 60 ventral striatal neurons showed sustained increases of activity before the occurrence of individual task events. In 43 of these neurons, activations specifically preceded the delivery of reward, independent of the movement or no-movement reaction. In a series of additional tests, these activations were time locked to the subsequent reward, disappeared within a few trials when reward was omitted, and were temporally unrelated to mouth movements. Changes in the appetitive value of the reward liquid modified the magnitude of activations, suggesting a possible relationship to the hedonic properties of the expected event. Activations also occurred when reward was delivered in a predictable manner outside of any behavioral task. These data suggest that neurons in the ventral striatum are activated during states of expectation of individual environmental events that are predictable to the subject through its past experience. The prevalence of activations related to the expectation of reward suggests that ventral striatal neurons have access to central representations of reward and thereby participate in the processing of information underlying the motivational control of goal-directed behavior.
Direct evidence is presented that training to change behavior initiates synthesis of specific species of mRNA in pyramidal nerve cells of CA3 of the hippocampus in rats. Reversal of handedness was used as goal-directed operant test and active controls. Newly synthesized poly(A) associated mRNA with S value of 25 and a stimulation of poly(A) lacking mRNA of 8--9 S and 16--17 S were found in the CA3 nerve cells of trained but not in active controls.
The neurological base of biological space and of spatial perception is discussed. The nervous system is viewed as a system controlling behaviour. Movements as elements of behaviour are guided movements: goal-directed, programmed and ordered in space. Perceptual space is derived from directional properties of behaviour. The sense organs are not 'doors of perception', transparent to the alleged properties of the environment. Rather they are used in a centrifugal sense--outward from the organism. They are instrumental in updating a 'map' of the outside world and of the organisms as part of that world. The map is, in essence, a projection of the organism's own behaviour modified by the regularities, constraints and supports encountered in the world. The role of the periphery varies from moment to moment with the organisational level of behaviour. Thus, the sensomotor system is operated for updating the map and also for calibrating movements. At a peripheral level it helps to level out irregularities encountered in the execution of simple movements. All these functions may take place at the same time. Taken together, these considerations serve as an explanation of the fact that we are able to determine the spatial properties of objects although the shape as such is not presented to the sensory surface of the body, nor are the various scanpaths of our exploratory movements a replica of the geometrical properties of the object.
Goal-directed grasping and manipulation of objects are human skills that depend on automatic sensory control in which predictive feed-forward mechanisms integrate somatosensory and visual signals with sensory-motor memory systems. Memory representations of physical and task-relevant properties of the object play a pivotal role. Anticipatory strategies are crucial when purposeful actions arise from learned relationships between afferent patterns and efferent commands. The development of even elementary precision grip skills is a protracted process not concluded until early adolescence. Not surprisingly, the neural control of manual actions engages most central nervous system areas known to be involved in motor control.
A neodissociative model of mind is better equipped than a social-psychological model to deal with the complexities of hypnosis, and of human behavior generally. It recognizes, as Coe's (1992) model does not, that behavior can be more automatically activated than strategically enacted. In particular, Coe's emphasis on human behavior as purposeful and goal directed does not distinguish between goal-directed behavior that serves a purpose, and goal-directed behavior that is performed on purpose. It is this distinction that permits goal-directed behavior to be dissociated from a person's conscious plans and intentions. In addition to offering a critique of Coe's "limited process" view of hypnosis, 4 main points are made in the interest of developing a slightly modified, neodissociation view of hypnosis. First, it is argued that goal-directed fantasies are more limited in their ability to mediate hypnotic responding than is commonly appreciated; as well, they do not seem to account for the nonvolitional quality of hypnotic responding. Second, it is argued that hypnotic ability is not unidimensional, with compliance and social influence more apt to account for the low than for the high hypnotizable's responsiveness to suggestion. Third, compared to low hypnotizables, the hypnotic responsiveness of high hypnotizables seems more likely to result from dissociated control. In other words, for high hypnotizables, hypnotic suggestions may often directly activate subsystems of cognitive control. Consequently, the need for executive initiative and effort to produce hypnotically suggested behavior is minimized, and such responses are therefore experienced as nonvolitional. Fourth and finally, while goal-directed fantasies typically accompany hypnotically suggested responses, they are in many cases more a marker of dissociated control than a mediator of suggested effects.
In 4 baboons and 3 macaques ablation of the frontal pole (area 10) as compared to other areas of the frontal cortex did not impair previously elaborated instrumental reflexes of different complexity and did not interfere with the elaboration of new ones. An increase in stability, speed, accuracy and intensity of conditioned reflexes was noted. The ablation did not result in motor or vegetative disturbances. In the general behaviour inhibitory elements disappeared along with an enhancement in motor goal-directed activity. It is suggested that frontal poles do not participate in closing-function but control conditioned reflexes and complex behaviour by means of inhibitory influences.
The explosion of knowledge set off by the characterization of endorphins and their receptors has created opportunities for new perspectives on a variety of phenomena. This brief essay examines one such phenomenon--the human febrile response--and proposes an alteration of the current model of the neuroendocrine circuitry controlling body temperature. Using behavioral thermoregulation as a starting point, we shall touch upon implications of this model for describing other forms of goal-directed motor activity.
An all-inhibitory network which learns by selective disconnection of synapses is described. This is similar to an 'associative net'; however, it is simpler in that its neurons do not need to perform arithmetical operations, and the net does not require additional threshold modulating neurons in order to cope with input patterns which are incomplete, or of differing sizes. This fundamental simplicity permits a greater variety and density of connections. These can multiply the capacity of the nets to learn complex sequences of patterns without being saturated. An "all-connected" net is described which has the holograph-like capacity to reconstruct the whole of an input pattern from part patterns without involving delays or threshold devices. All of these inhibitory nets can construct themselves by means of simple random growth processes, without incurring any loss of learning capacity of holographic properties. Similarly, synapses can be allowed to potentiate with use, so that reaction times are progressively reduced by practice, without any reduction in the quality of the performance. Inhibitory connections between arrays can give patterns in one array control over the allocation of channels in which lower arrays store learned information. A description is given of a model, decentralised, inhibitory hierarchy consisting of inter-connected arrays which can learn to execute goal-directed TOTE-type programs of behaviour by means of a simple 'putting-through' procedure.
We have answered technical criticisms of our work in which anticholinergic agents were added to ongoing neuroleptic treatment in an ABA' research design. The suggested analysis of variance for repeated measures of the three periods is inappropriate because of the expected carryover effects from continuous neuroleptic treatment. The multivariate analysis of various parameters seems unsuitable because homogeneity of covariance cannot be ensured due to the heterogeneity of schizophrenia and the diverse factors represented in the psychopathology measures. We have summarized the results of recent parametric and nonparametric analyses of combined data from our three studies to show that the significant effects clearly pointed to therapeutic antagonism between anticholinergic agents and neuroleptics. We suggest that cholinergic neurons may be part of some crucial discriminative control mechanisms in the brain organization that are ineffective in schizophrenia and lead to a relative overactivity of the opposing catecholaminergic neurons in the midbrain-limbic circuitry which promote repetition of behaviors in goal-directed activity.
The study examined the effect of monetary incentive on the performance of five tasks after two heterogeneous groups of experienced users of cannabis and previously naive subjects had smoked placebo material and two dose levels of cannabis. The performance of the motivated subjects was compared with that of two non-motivated matched groups. Dose-related impairment was found on four of the five tasks, supporting previous findings of cannabis-induced impairment of short-term memory, goal-directed behavior and choice reaction times. Results for three of the tasks suggested that the performance of the motivated subjects was less affected by the drug than was the performance of the non-motivated subjects. There was no difference between the performance of subjects naive and experienced with respect to drug use.
Neurons of the rostral part of inferior premotor cortex of the monkey discharge during goal-directed hand movements such as grasping, holding, and tearing. We report here that many of these neurons become active also when the monkey observes specific, meaningful hand movements performed by the experimenters. The effective experimenters' movements include among others placing or retrieving a piece of food from a table, grasping food from another experimenter's hand, and manipulating objects. There is always a clear link between the effective observed movement and that executed by the monkey and, often, only movements of the experimenter identical to those controlled by a given neuron are able to activate it. These findings indicate that premotor neurons can retrieve movements not only on the basis of stimulus characteristics, as previously described, but also on the basis of the meaning of the observed actions.
The functions of the central monoamines Norepinephrine (NE) and Serotonin (5HT) can be clarified by the study of behaviors of rats administered selective monoamine toxins. In his home environment the low NE rat has drive deficits and is lethargic, tending to remain in his burrow, but in novel environments this animal acts less frightened than Controls. The low 5HT rat is conversely active and exploratory in familiar environments but frightened in novel environments. These two animals model aspects of depression and anxiety, respectively. 5HT can be thought of as placing the brain into a state of consciousness appropriate for an animal in his nest (i.e., 5HT neurons act as relaxers), and as involved in a type of positive affect related to security, whereas NE neurons are dominant when an animal is vigilant, foraging out in the environment and are involved in a type of positive affect related to goal-directed approach arousal. Monoamine toxins may be produced when the behaviors elicited by these central neuronal systems are negatively reinforced (extinguished).
BACKGROUND: The OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention for Learning) theory is a motor learning framework proposing that optimizing intrinsic motivation enhances motor performance and learning. The theory identifies three key components-Enhanced Expectancies (EE), Autonomy Support (AS) and External Focus of Attention (EF)-which facilitate more efficient, goal-directed movement. These components have been shown to improve motor outcomes in limb-based tasks; however, their application to respiratory training, particularly in clinical contexts such as voice and swallowing therapy in patients with Parkinson's disease (pwPD), has not yet been systematically explored. AIMS: This study aimed to investigate whether implementing OPTIMAL theory strategies during a respiratory muscle strength training (RMST) task improves immediate respiratory motor performance in healthy adults and pwPD. Additionally, we aimed to examine the effects of these strategies on motivation and cognitive engagement. METHODS: This quasi-randomized, single-session trial included 47 participants: Healthy CONTROL (n = 17), Healthy OPTIMAL (n = 16) and PD OPTIMAL (n = 14). Healthy participants were quasi-randomly assigned to either intervention or control conditions, whereas pwPD completed the intervention only. All participants completed a single respiratory session that included baseline, practice and retention phases. Outcome measures included peak expiratory flow, cough peak expiratory flow, cognitive engagement (EEG-based Cognitive Engagement Index) and self-administered motivation questionnaire. OUTCOMES AND RESULTS: Exhalation force improved from baseline to retention in the Healthy OPTIMAL group (baseline: M = 296 L/min; retention: M = 338 L/min; p < 0.001) and the PD OPTIMAL group (baseline: M = 315 L/min; retention: M = 370 L/min; p < 0.0001), but not in the Healthy CONTROL group (p > 0.05). No significant changes in cough strength were observed in any group. No correlations were found between cognitive engagement and exhalation force or motivation scores. However, motivation increased more in the Healthy OPTIMAL group (Questionnaire 1: M = 57.2; Questionnaire 2: M = 60.7) and the PD OPTIMAL group (Questionnaire 1: M = 60.1; Questionnaire 2: M = 62.8) than in the Healthy CONTROL group (Questionnaire 1: M = 61.1; Questionnaire 2: M = 62.5). CONCLUSIONS AND IMPLICATIONS: Implementing the OPTIMAL theory enhances immediate respiratory motor performance in both healthy participants and pwPD. OPTIMAL theory has clinical value in voice and swallowing therapy, although further research is needed to establish long-term efficacy and clinical impact. WHAT THIS PAPER ADDS: What is already known on the subject Motivation is a critical factor in rehabilitation. The OPTIMAL theory has been shown to improve both motivation and motor performance in limb-based tasks. Its impact on respiratory training, however, has not been previously examined. What this paper adds to the existing knowledge This study shows that applying OPTIMAL strategies during a respiratory muscle strength training task significantly improved peak expiratory flow in both healthy adults and people with Parkinson's disease. What are the potential or clinical implications of this work? Integrating the OPTIMAL theory principles into respiratory therapy may enhance motor outcomes, supporting voice, swallowing and cough rehabilitation.
By using a mathematical model and experiments involving electrical simulation of antagonistic muscles, we have formed the hypothesis (Wierzbicka et al. 1986) that in one-joint movements the antagonist muscle not only provides braking torque but also controls movement time. To get additional experimental support for this hypothesis, we studied elbow flexion movements performed by patients with spinal cord injury at the C5-6 level who had relatively normal strength in their biceps muscle and little or no voluntary control of the triceps. Seven quadriplegic patients and six control subjects performed elbow flexion movements of 10 degrees, 20 degrees, and 30 degrees "as fast and accurately as possible". Despite the lack of antagonist, patients used the same "pulse height" strategy as control subjects to scale their responses with movement amplitude. However, patients' movement time was on average twice that of control subjects, and durations of both accelerative and decelerative phases of movement were increased. Movement speed and acceleration were reduced to 20-50% of the corresponding values of control subjects. Patients tended to overshoot the target to a larger extent than control subjects, particularly 10 degrees targets, with nearly twice the error. We performed the same experiments using an external torque motor to assist the weak triceps. When a constant extensor torque of 2.5 or 5 Nm was provided by the motor, patients were able to move faster, and movement accuracy improved to within the normal range. These results provide direct evidence that the lack of an antagonist has an important effect on completion time and accuracy of fast goal-directed movements.
BACKGROUND: Visuomotor integration coordinates visual and motor cortical activity to produce goal-directed responses and can be indexed by Rolandic Mu-rhythm suppression and visual evoked potential (VEP) P100 parameters. Perceptual-motor training improves visuomotor performance, and transcranial direct current stimulation (tDCS) over primary motor cortex (M1) has been reported to enhance motor learning when paired with training. This study examined whether anodal M1 tDCS augments the effects of Senaptec visuomotor training in healthy adults. METHODS: Sixty participants were randomized to active anodal tDCS (five 10-minute sessions, 1 mA; n = 31) or sham (n = 29) over M1 immediately before each Senaptec training session; 53 completed all sessions and post-testing. Outcomes were Mu-suppression ratios, VEP P100 latency and amplitude, and Senaptec measures of visual sensitivity and visuomotor control. RESULTS: Active tDCS produced no augmentation of any outcome, with no significant group × time interaction for any measure, consistent across composite and task-level analyses. Training alone produced no change in Mu suppression or visuomotor control. By contrast, both groups showed significant training-related gains in visual sensitivity, including near-far quickness and stereopsis, accompanied by shorter P100 latencies and larger amplitudes, indicating more efficient early visual processing. CONCLUSIONS: A clear dissociation emerged: training produced robust improvements in early visual processing, whereas neither tDCS nor training altered sensorimotor (Mu) or visuomotor-control measures. The tDCS results should be interpreted cautiously given the modest dose and limited power to detect small effects, rather than as evidence of inefficacy. Tablet-based perceptual training enhanced visual processing independent of neuromodulation.