Biomedical subjects

M Symmons

Publications and source records attributed to M Symmons.

3 recordsLinked to original sources

PubMed2000

Raised line drawings are spontaneously explored with a single finger.

In this study we examine the strategies used by blindfolded subjects asked to freely explore raised line drawings and identify what is depicted in them. We were particularly interested in how often a single finger is spontaneously used because in several studies subjects are forced to use only one fingertip and the extent to which this restriction may depress haptic perception is unclear. The results suggest that despite a variety of strategies, people 'naturally' use single fingertips sufficiently often to allow confidence in conclusions that are based on studies imposing this restriction.

Adolescent↗

PubMed2000

The TDS: a new device for comparing active and passive-guided touch.

A problem when comparing active and passive tactile perception of two-dimensional (2-D) stimuli is matching the active and passive tasks on all variables except the one of interest--active versus passive touch. A new computer-controlled device--the tactile display system (TDS)--has been developed to deal with this problem. The TDS tracks an "active" subject's fingertip movements during exploration of a raised line drawing and digitally records this spatio-temporal information. It then guides a passive participant's fingertip over the same path, matching for location and speed. Any difference in performance can thus be attributed to the different conditions (active versus passive) because other variables are held constant.

Blindness↗

PubMed1984

Microcomputers to control the pH of growing micro-organisms.

Negative feedback control can usefully be used in biochemistry for a variety of purposes. Two examples are presented which utilize microcomputers to generate the transfer function of the feedback loop. The first demonstrates the control of NADH concentration during an enzymic reaction, and the second shows that if the pH is held constant whilst growing E. coli the yield can be increased. In both these cases it is convenient, even essential, to use a computer because computers are both very stable over the long term and the feedback transfer function can be accurately and quickly specified.

Cell Division↗