A simple and inexpensive computer-compatible shock circuit

A circuit for computer control of shock stimulation that uses an optically isolated triac is described.     

A biphasic 60-Hz synchronizer circuit for the recording of visually evoked responses in high-noise environments

A simple synchronizer clock circuit is described that aids in the rejection of 60-Hz noise from evoked potential measurements.     

Taste perceptual circuit for the generation of autonomous responses in virtual creatures

BraLearning is one of the most complex cognitive processes that living beings have. This process is distributed within the brain and each independent cognitive function contributes to a small or large extent to it. Particularly, affective learning is a process that allows us to identify stimuli in the environment and discriminate them based on our tastes or preferences. Within this work we will address a type of affective evaluation generated by the perceptual circuit of taste that allows us to determine flavors from the environment and how this information becomes part of the perceptual affective evaluation. We will start this work by identifying other computational works that address affective processes oriented to taste or that involve some other affective evaluation. Subsequently, we analyze of neuroscientific information that allows us to build an informal model of the perceptual circuit of taste. Finally, we propose a cognitive architecture for the generation of autonomous responses oriented to taste in virtual creatures and we will demonstrate its functionality through an implementation of this model in some case studies through distributed modules and discuss the results obtained.     

A programmable circuit for varying light intensity

An inexpensive circuit is described for the control of light intensity. The control is obtained by a method that produces no color changes and may be programmed by any system that can express itself in four-digit binary numbers.     

A CRT blanking circuit for video terminals

A simple and inexpensive modification for the ADDS 980 video terminal is described which permits the characters displayed on the CRT to be blanked and restored (under software control). This circuit is useful in applications, such as RT measurement, where precise definition of stimulus onset is important. The technique described is general enough to be applied to a variety of other video terminals.     

A simple tachistoscope for student labs

An inexpensive tachistoscope for student labs is described that utilizes a camera shutter to control exposure duration and a potentiometer to vary light intensity. Stimuli can be drawn or typed on 3 x 5 index cards.     

A simple procedure for rearranging matrices

Guttman's scalogram board technique for reordering the columns and rows of a matrix is described and its disadvantages are pointed out. A simple and inexpensive procedure for doing the same job without these disadvantages is outlined.I am grateful to Professor Jozef Cohen of the University of Illinois for a five-minute conversation which greatly simplified the procedure described here.     

Persistent and emergent cardiac responses elicited by simple stimuli

Heart rate and respiration were recorded as rabbits were exposed to visual and auditory events: light-on, light-off, light-change, noise-on, noise-off and noise-change. Each event lasted one second. One kind of stimulus event was presented ten times each session. Each kind of event was used for five sessions. On the following sessions (forty) two kinds of stimulus events were continued and used during the same session in order to introduce novelty. A beat-to-beat analysis of heart rate with corresponding respiration analysis showed (1) that rise and decay time of the reactions tended to decrease although magnitude might increase with repetition of the stimulus, (2) that some reactions elicited by some stimuli persisted beyond 400 trials, (3) that some reactions, not seen at first, appeared after 20–30 trials, (4) that respiration could be ruled out as a necessar causal factor for the heart rate changes, (5) that rate changes are specific to the modality or quality of the stimulus (e.g. noise-on vs. noiseoff or light-on), (6) that some reactions may be attenuated by stimulus novelty.     

Attentional localization prior to simple and directed manual responses

The relationship between attention and the programming of motor responses was investigated, using a paradigm in which the onsets of targets for movements were preceded by peripheral attentional cues. Simple (button release) and reaching manual responses were compared under conditions in which the subjects either made saccades toward the target location or refrained from making eye movements. The timing of the movement onset was used as the dependent measure for both simple and reaching manual responses. Eye movement latencies were also measured. A follow-up experiment measured the effect of the same peripheral cuing procedure on purely visual processes, using signal detection measures of visual sensitivity and response bias. The results of the first experiment showed that reaction time (RT) increased with the distance between the cued and the target locations. Stronger distance effects were observed when goal-directed responses were required, which suggests enhanced attentional localization of target positions under these conditions. The requirement to generate an eye movement response was found to delay simple manual RTs. However, mean reaching RTs were unaffected by the eye movement condition. Distance gradients on eye movement latencies were relatively shallow, as compared with those on goal-directed manual responses. The second experiment showed that the peripheral cue had only a very small effect on visual detection sensitivity in the absence of directed motor responses. It is concluded that cue-target distance effects with peripheral cues are modulated by the motor-programming requirements of the task. The effect of the peripheral cue on eye movement latencies was qualitatively different from that observed on manual RTs, indicating the existence of separate neural representations underlying both response types. At the same time, the interactions between response modalities are consistent with a supramodal representation of attentional space, within which different motor programs may interact.